Similar Datasets
Project description:By using transgenic zebrafish lines Tg(nxk2.5:GFP) (Witzel et al. 2012) and Tg(myl7:EGFP) (D'Amico et al. 2007), we have characterized chromatin accessibility of FACS-isolated CM (GFP+) from developing zebrafish heart at 24, 48 and 72 hpf, corresponding to heart tube formation, chamber formation and differentiation and heart maturation, respectively. GFP- cells were used as a control. We have identified cardiac regulatory networks playing a crucial role in heart morphogenesis. To validate their importance in heart development, we employed zebrafish mutants of cardiac transciption factors Gata5, Hand2 and Tbx5a, the disruption of which were previously linked to impaired migration of the cardiac primordia to the embryonic midline, reduced number of myocardial precursors and failure of heart looping, respectively (Reiter et al. 1999; Yelon et al. 2000; Garrity et al. 2002). ATAC-seq was performed from homozygous gata5tm236a/tm236a, tbx5am21/ m21, hand2s6/s6 mutant 72 hpf embryos in Tg(myl7:EGFP) genetic background. Homozygous mutant embryos for analyses were selected on the basis of their phenotypes of cardia bifida (gata5tm236a/tm236a, hand2s6/s6) or heart-string (tbx5am21/ m21) .
2019-01-10 | GSE120237 | GEO
Project description:Genome-wide chromatin accessibility profile of zebrafish cardiomyocytes throughout heart development
| PRJNA492281 | ENA
Project description:Transcriptome profile and Genome-wide chromatin accessibility profile of zebrafish cardiomyocytes throughout heart development
| PRJNA492279 | ENA
Project description:By using transgenic zebrafish lines Tg(nxk2.5:GFP) (Witzel et al. 2012) and Tg(myl7:EGFP) (D'Amico et al. 2007), we have characterized transcriptomic profile of FACS-isolated CM (GFP+) from developing zebrafish heart at 24, 48 and 72 hpf, corresponding to heart tube formation, chamber formation and differentiation and heart maturation, respectively. GFP- cells were used as a control. We have identified cardiac regulatory networks playing a crucial role in heart morphogenesis. To validate their importance in heart development, we employed zebrafish mutants of cardiac transciption factors Gata5, Hand2 and Tbx5a, the disruption of which were previously linked to impaired migration of the cardiac primordia to the embryonic midline, reduced number of myocardial precursors and failure of heart looping, respectively (Reiter et al. 1999; Yelon et al. 2000; Garrity et al. 2002). RNA-seq was performed from homozygous gata5tm236a/tm236a, tbx5am21/ m21, hand2s6/s6 mutant 72 hpf embryos in Tg(myl7:EGFP) genetic background. Homozygous mutant embryos for analyses were selected on the basis of their phenotypes of cardia bifida (gata5tm236a/tm236a, hand2s6/s6) or heart-string (tbx5am21/ m21) .
2019-01-10 | GSE120236 | GEO
Project description:Transcriptomic profile of zebrafish cardiomyocytes throughout heart development
| PRJNA492280 | ENA
Project description:Transcriptional and epigenetic characterization of melanocytes and melanoma cells isolated from their in vivo context promises to unveil key differences between these developmentally related normal and cancer cell populations. We therefore engineered an enhanced Danio rerio (zebrafish) melanoma model with fluorescently labeled melanocytes to allow for isolation of normal (wild type) and premalignant (BRAFV600E-mutant) populations for comparison to fully transformed BRAFV600E-mutant, p53 loss-of-function melanoma cells. Using fluorescence-activated cell sorting to isolate these populations, we performed high-quality RNA- and ATAC-seq on sorted zebrafish melanocytes vs. melanoma cells, which we provide as a resource here. Melanocytes had consistent transcriptional and accessibility profiles, as did melanoma cells. Comparing melanocytes and melanoma, we note 4128 differentially expressed genes and 56,936 differentially accessible regions with overall gene expression profiles analogous to human melanocytes and the pigmentation melanoma subtype. Combining the RNA- and ATAC-seq data surprisingly revealed that increased chromatin accessibility did not always correspond with increased gene expression, suggesting that though there is widespread dysregulation in chromatin accessibility in melanoma, there is a potentially more refined gene expression program driving cancerous melanoma. These data serve as a resource to identify candidate regulators of the normal vs. diseased states in a genetically controlled in vivo context.
| S-EPMC8727958 | biostudies-literature
Project description:Genome-wide chromatin state underlies gene expression potential and cellular function. Epigenetic features and nucleosome positioning contribute to the accessibility of DNA, but widespread regulators of chromatin state are largely unknown. Our study investigates how coordination of ANP32E and H2A.Z contributes to genome-wide chromatin state in mouse fibroblasts. We define H2A.Z as a universal chromatin accessibility factor, and demonstrate that ANP32E antagonizes H2A.Z accumulation to restrict chromatin accessibility genome-wide. In the absence of ANP32E, H2A.Z accumulates at promoters in a hierarchical manner. H2A.Z initially localizes downstream of the transcription start site, and if H2A.Z is already present downstream, additional H2A.Z accumulates upstream. This hierarchical H2A.Z accumulation coincides with improved nucleosome positioning, heightened transcription factor binding, and increased expression of neighboring genes. Thus, ANP32E dramatically influences genome-wide chromatin accessibility through subtle refinement of H2A.Z patterns, providing a means to reprogram chromatin state and to hone gene expression levels.
| S-EPMC7546623 | biostudies-literature
Project description:To better understand genome regulation, it is important to uncover the role of transcription factors in the process of chromatin structure establishment and maintenance. Here we present a data-driven approach to systematically characterise transcription factors that are relevant for this process. Our method uses a linear mixed modelling approach to combine datasets of transcription factor binding motif enrichments in open chromatin and gene expression across the same set of cell lines. Applying this approach to the ENCODE dataset, we confirm already known and imply numerous novel transcription factors that play a role in the establishment or maintenance of open chromatin. In particular, our approach rediscovers many factors that have been annotated as pioneer factors.
| S-EPMC5261565 | biostudies-literature
Project description:The spatial organization of chromosomes is critical in establishing gene expression programs. We generated in situ Hi-C maps throughout zebrafish development to gain insight into higher-order chromatin organization and dynamics. Zebrafish chromosomes segregate in active and inactive chromatin (A/B compartments), which are further organized into topologically associating domains (TADs). Zebrafish A/B compartments and TADs have genomic features similar to those of their mammalian counterparts, including evolutionary conservation and enrichment of CTCF binding sites at TAD borders. At the earliest time point, when there is no zygotic transcription, the genome is highly structured. After zygotic genome activation (ZGA), the genome loses structural features, which are re-established throughout early development. Despite the absence of structural features, we see clustering of super-enhancers in the 3D genome. Our results provide insight into vertebrate genome organization and demonstrate that the developing zebrafish embryo is a powerful model system to study the dynamics of nuclear organization.
| S-EPMC6047509 | biostudies-literature
Project description:Nucleosomal DNA is thought to be generally inaccessible to DNA-binding factors, such as micrococcal nuclease (MNase). Here, we digest Drosophila chromatin with high and low concentrations of MNase to reveal two distinct nucleosome types: MNase-sensitive and MNase-resistant. MNase-resistant nucleosomes assemble on sequences depleted of A/T and enriched in G/C-containing dinucleotides, whereas MNase-sensitive nucleosomes form on A/T-rich sequences found at transcription start and termination sites, enhancers and DNase I hypersensitive sites. Estimates of nucleosome formation energies indicate that MNase-sensitive nucleosomes tend to be less stable than MNase-resistant ones. Strikingly, a decrease in cell growth temperature of about 10°C makes MNase-sensitive nucleosomes less accessible, suggesting that observed variations in MNase sensitivity are related to either thermal fluctuations of chromatin fibers or the activity of enzymatic machinery. In the vicinity of active genes and DNase I hypersensitive sites nucleosomes are organized into periodic arrays, likely due to 'phasing' off potential barriers formed by DNA-bound factors or by nucleosomes anchored to their positions through external interactions. The latter idea is substantiated by our biophysical model of nucleosome positioning and energetics, which predicts that nucleosomes immediately downstream of transcription start sites are anchored and recapitulates nucleosome phasing at active genes significantly better than sequence-dependent models.
| S-EPMC4756854 | biostudies-other