ChIP-seq of H3K4me3 and H3K27me3 histone marks in the hypothalamus of 35 days-old control and thermally-manipulated chickens
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ABSTRACT: The experiment aimed at investigating the profiles of two histone marks (H3K27me3 and H3K4me3) in hypothalamus tissues 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: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:Long non-coding RNAs (lncRNAs) comprise a diverse class of transcripts that structurally resemble mRNAs but do not encode proteins. Recent genome-wide studies in human and mouse have annotated lncRNAs expressed in cell lines and adult tissues, but a systematic analysis of lncRNAs expressed during vertebrate embryogenesis has been elusive. To identify lncRNAs with potential functions in vertebrate embryogenesis, we performed a time series of RNA-Seq experiments at eight stages during early zebrafish development. We reconstructed 56,535 high-confidence transcripts in 28,912 loci, recovering the vast majority of expressed RefSeq transcripts, while identifying thousands of novel isoforms and expressed loci. We defined a stringent set of 1,133 non-coding multi-exonic transcripts expressed during embryogenesis. These include long intergenic ncRNAs (lincRNAs), intronic overlapping lncRNAs, exonic antisense overlapping lncRNAs, and precursors for small RNAs (sRNAs). Zebrafish lncRNAs share many of the characteristics of their mammalian counterparts: relatively short length, low exon number, low expression, and conservation levels comparable to introns. Subsets of lncRNAs carry chromatin signatures characteristic of genes with developmental functions. The temporal expression profile of lncRNAs revealed two novel properties: lncRNAs are expressed in narrower time windows than protein-coding genes and are specifically enriched in early-stage embryos. In addition, several lncRNAs show tissue-specific expression and distinct subcellular localization patterns. Integrative computational analyses associated individual lncRNAs with specific pathways and functions, ranging from cell cycle regulation to morphogenesis. Our study provides the first comprehensive identification of lncRNAs in a vertebrate embryo and forms the foundation for future genetic, genomic and evolutionary studies. ChIP-Seq for H3K4me3 and H3K27me3 at zebrafish shield stage.
Project description:PPAR? promotes adipogenesis while Wnt proteins inhibit adipogenesis. However, the mechanisms that control expression of these positive and negative master regulators of adipogenesis remain incompletely understood. By genome-wide histone methylation profiling in preadipocytes, we find that among gene loci encoding adipogenesis regulators, histone methyltransferase (HMT) G9a-mediated repressive epigenetic mark H3K9me2 is enriched on the entire PPAR? locus. H3K9me2 and G9a levels decrease during adipogenesis, which correlates inversely with induction of PPAR?. Removal of H3K9me2 by G9a deletion enhances chromatin opening and binding of adipogenic transcription factor C/EBP-beta to PPAR? promoter, which promotes PPAR? expression. Interestingly, G9a represses PPAR? expression in an HMT activity-dependent manner but facilitates Wnt10a expression independent of its enzymatic activity. Consistently, deletion of G9a or inhibiting G9a HMT activity promotes adipogenesis. Finally, deletion of G9a in mouse adipose tissues increases adipogenic gene expression and tissue weight. Thus, by inhibiting PPAR? expression and facilitating Wnt10a expression, G9a represses adipogenesis. Examination of 3 different histone modification changes in 3T3-L1 preadipocytes
Project description:To identify chromatin alterations in primary gastric adenocarcionomas, we performed nano-scale chromatin immunoprecipitation-sequencing (Nano-CHiPseq) of histone modifications in 5 gastric cancers and matched normal tissues, We identified hundreds of somatically-altered promoters (marked by H3K4me3) and enhancers (H3K4me1). The majority of cancer-associated promoters localized to genomic sites lacking previously-annotated transcription start sites (“cryptic promoters”), driving high expression of nearby genes implicated in gastrointestinal cancers, embryonic development, and tissue specification. Our findings demonstrate the feasibility of performing chromatin profiling on solid tumors where tissue is limiting, to identify in non-coding regions regulatory elements, transcriptional patterns and genetic variants associated with cancer. We propose a pervasive role for cryptic promoters in the reactivation of early developmental programs in gastric cancer, and the potential utility of cryptic promoters as biomarkers of malignancy. Five gastric cancer tumor normal pairs are profiling in multiple number of chromatin marks
Project description:We used NimbleGen human CpG/promoter microarrays for profiling epigenetic changes (DNA methylation, H3K27me3 and H3K4me3 marks) in colon tumors (Duke's stage II) and matching mucosa samples from patients. Analysis of DNA methylation was done by using the methylated CpG island recovery assay (MIRA) technique with further hybridization versus input on NimbleGen human CpG/promoter microarrays. For profiling of H3K27me3 and H3K4me3 marks, we performed chromatin immunoprecipitation with H3K27me3 (#07-449, Millipore) and H3K4me3 (#39159, Active Motif) antibodies and further hybridized versus input on NimbleGen human CpG/promoter microarrays. All experiments were performed simultaneously for matching tissue samples.
Project description:After wounding in plants, a vast and rapid transcriptional reprogramming takes place. Interestingly, this reprogramming includes the reactivation of developmental regulators that in mature tissue normally are epigenetically repressed. We evaluated which histone modifications are associated with this rapid increase of these developmental regulators.
Project description:This SuperSeries is composed of the following subset Series: GSE32898: Comprehensive identification of long non-coding RNAs expressed during zebrafish embryogenesis [RNA_seq] GSE32899: Comprehensive identification of long non-coding RNAs expressed during zebrafish embryogenesis [ChIP_Seq] Refer to individual Series
Project description:As sex determines mammalian development, understanding the nature and developmental dynamics of the sexually dimorphic transcriptome is important. To explore this, we generated 72 genome-wide RNA-seq profiles from mouse eight-cell embryos, late gestation and adult livers, together with 4 ground-state pluripotent embryonic (ES) cell lines from which we generated both RNA-seq and multiple ChIP-seq profiles. We complemented this with previously published data to yield 5 snap-shots of pre-implantation development, late-gestation placenta and somatic tissue and multiple adult tissues for integrative analysis. We define a high-confidence sex-dimorphic signature of 56 genes in eight-cell embryos. Sex-chromosome-linked components of this signature are largely conserved throughout pre-implantation development and ES cells, whilst the autosomal component is more dynamic. Sex-biased gene expression is reflected by enrichment for activating and repressive histone modifications. The eight-cell signature is largely non-overlapping with that defined from fetal liver, neither was it correlated with liver or other adult tissues analysed. Fetal and adult liver gene expression signatures are also substantially different, yet a core set of common genes showing modest dimorphic expression was identified. Dramatic sex-specific expression of olfactory receptors was found in fetal liver. Sex-biased expression differences unique to adult liver were enriched for growth hormone-responsiveness. The majority of sex-chromosome based differences identified from eight-cell embryos are also present in placenta but not somatic tissue at the same gestational age. This systematic study identifies three distinct phases of sex dimorphism throughout mouse development, and has significant implications for understanding the developmental origins of sex-specific phenotypes and disease in mammals. ChIP seq of Es Cell