Systemic gain and loss of chromatin architecture throughout zebrafish development [4C]
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA414424 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Systemic Loss and Gain of Chromatin Architecture throughout Zebrafish Development.
| PRJNA414421 | ENA
Project description:Systemic gain and loss of chromatin architecture throughout zebrafish development [Hi-C]
| PRJNA414425 | ENA
Project description:Chromosomes are three-dimensional structures in the nucleus that are organized at multiple levels. Studies in mammals have shown that chromosomes segregate in active and inactive compartments (A and B, resp.). A compartments have high transcription activity, high GC-content and replicate early in S-phase. B compartments on the other hand are transcriptionally inactive, have low CG content are often found at the nuclear periphery. Every compartment is further divided into megabase-sized Topologically Associated Domains (TADs), the functional units of gene regulation. Regions within such a domain preferentially interact with each other. TAD positions are conserved between mouse and human genomes. However, it is unclear if non-mammalian vertebrates also show these organizational features and how these change throughout development. We have generated Hi-C maps for zebrafish embryos and show that the structural features of mammalian genomes (A/B-compartments and TADs) are also found in this species. We find that the genes within TADs show spatial co-expression. Moreover, the order of genes within a TAD is conserved to other vertebrate species. One of the key features of development is the switch from maternally loaded mRNAs to the transcriptional activation of the zygotic genome, known as Zygotic Genome Activation (ZGA). Prior to ZGA we see both TADs and compartments. Paradoxically, after the initiation of transcription, TADs and compartments completely disappear. These features are progressively re-established in the following developmental stages. Our results show that chromosome conformation can be formed independent of transcription. Analysis of active enhancer and promoter marks after ZGA showed that promoters and enhancers are enriched at future TAD-boundaries. Later in time, when TADs are present, the enrichment of active enhancers at the TAD-boundaries is lost. These data suggest that proximal enhancer-promoter interactions are needed for gene regulation when TADs are not in place. The loss of both TADs and compartments represent an interesting avenue for the further study of factors involved in the formation of the structural features of vertebrate chromosomes.
2018-07-01 | GSE105014 | GEO
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:Chromosomes are three-dimensional structures in the nucleus that are organized at multiple levels. Studies in mammals have shown that chromosomes segregate in active and inactive compartments (A and B, resp.). A compartments have high transcription activity, high GC-content and replicate early in S-phase. B compartments on the other hand are transcriptionally inactive, have low CG content are often found at the nuclear periphery. Every compartment is further divided into megabase-sized Topologically Associated Domains (TADs), the functional units of gene regulation. Regions within such a domain preferentially interact with each other. TAD positions are conserved between mouse and human genomes. However, it is unclear if non-mammalian vertebrates also show these organizational features and how these change throughout development. We have generated Hi-C maps for zebrafish embryos and show that the structural features of mammalian genomes (A/B-compartments and TADs) are also found in this species. We find that the genes within TADs show spatial co-expression. Moreover, the order of genes within a TAD is conserved to other vertebrate species. One of the key features of development is the switch from maternally loaded mRNAs to the transcriptional activation of the zygotic genome, known as Zygotic Genome Activation (ZGA). Prior to ZGA we see both TADs and compartments. Paradoxically, after the initiation of transcription, TADs and compartments completely disappear. These features are progressively re-established in the following developmental stages. Our results show that chromosome conformation can be formed independent of transcription. Analysis of active enhancer and promoter marks after ZGA showed that promoters and enhancers are enriched at future TAD-boundaries. Later in time, when TADs are present, the enrichment of active enhancers at the TAD-boundaries is lost. These data suggest that proximal enhancer-promoter interactions are needed for gene regulation when TADs are not in place. The loss of both TADs and compartments represent an interesting avenue for the further study of factors involved in the formation of the structural features of vertebrate chromosomes.
2018-07-01 | GSE105013 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below.
2018-07-01 | GSE105015 | GEO
Project description:Background: The packaging of long chromatin fibres in the nucleus poses a major challenge, as it must fulfil both physical and functional requirements. Until recently, insight into the chromosomal architecture of plants was mainly provided by cytogenetic studies. Complementary to these analyses, chromosome conformation technologies promise to refine and improve our view on chromosomal architecture and to provide a more generalised description of nuclear organization. Results: Employing circular chromosome conformation capture (4C), this study describes chromosomal architecture in Arabidopsis nuclei from a genome-wide perspective. Surprisingly, the linear organisation of chromosomes is reflected in the genome-wide interactome. In addition, we studied the interplay of the interactome and epigenetic marks and report that the heterochromatic knob on the short arm of chromosome 4 (hk4s) maintained a pericentromere-like interaction profile and interactome despite its euchromatic surrounding. Conclusion: Despite the extreme condensation that is necessary to pack the chromosomes into the nucleus, the Arabidopsis genome appears to be packed in a predictive manner, according to the following criteria: (i) heterochromatin and euchromatin represent two distinct interactomes, (ii) interactions between chromosomes correlates with the linear position on the chromosome arm, and (iii) distal chromosome regions have a higher potential to interact with other chromosomes. This study includes circular chromosome conformation capture (4C) sequencing information of 13 samples, present in two batches, each present in duplicates (A and B). The individual 4C sequencing information can be retrieved by the 4C primer sequence, given in the 4C primer information file.
2013-11-01 | E-GEOD-50181 | biostudies-arrayexpress
Project description:4C-Seq has proven to be a powerful technique to identify genome-wide interactions with a single locus of interest (or "bait") that can be important for gene regulation. However, analysis of 4C-Seq data is complicated by the many biases inherent to the technique. An important consideration when dealing with 4C-Seq data is the differences in resolution of signal across the genome that result from differences in 3D distance separation from the bait. This leads to the highest signal in the region immediately surrounding the bait and increasingly lower signals in far-cis and trans. Another important aspect of 4C-Seq experiments is the resolution, which is greatly influenced by the choice of restriction enzyme and the frequency at which it can cut the genome. Thus, it is important that a 4C-Seq analysis method is flexible enough to analyze data generated using different enzymes and to identify interactions across the entire genome. Current methods for 4C-Seq analysis only identify interactions in regions near the bait or in regions located in far-cis and trans, but no method comprehensively analyzes 4C signals of different length scales. In addition, some methods also fail in experiments where chromatin fragments are generated using frequent cutter restriction enzymes. Here, we describe 4C-ker, a Hidden-Markov Model based pipeline that identifies regions throughout the genome that interact with the 4C bait locus. In addition, we incorporate methods for the identification of differential interactions in multiple 4C-seq datasets collected from different genotypes or experimental conditions. Adaptive window sizes are used to correct for differences in signal coverage in near-bait regions, far-cis and trans chromosomes. Using several datasets, we demonstrate that 4C-ker outperforms all existing 4C-Seq pipelines in its ability to reproducibly identify interaction domains at all genomic ranges with different resolution enzymes.
2016-02-27 | GSE77645 | GEO
Project description:4C-Seq has proven to be a powerful technique to identify genome-wide interactions with a single locus of interest (or "bait") that can be important for gene regulation. However, analysis of 4C-Seq data is complicated by the many biases inherent to the technique. An important consideration when dealing with 4C-Seq data is the differences in resolution of signal across the genome that result from differences in 3D distance separation from the bait. This leads to the highest signal in the region immediately surrounding the bait and increasingly lower signals in far-cis and trans. Another important aspect of 4C-Seq experiments is the resolution, which is greatly influenced by the choice of restriction enzyme and the frequency at which it can cut the genome. Thus, it is important that a 4C-Seq analysis method is flexible enough to analyze data generated using different enzymes and to identify interactions across the entire genome. Current methods for 4C-Seq analysis only identify interactions in regions near the bait or in regions located in far-cis and trans, but no method comprehensively analyzes 4C signals of different length scales. In addition, some methods also fail in experiments where chromatin fragments are generated using frequent cutter restriction enzymes. Here, we describe 4C-ker, a Hidden-Markov Model based pipeline that identifies regions throughout the genome that interact with the 4C bait locus. In addition, we incorporate methods for the identification of differential interactions in multiple 4C-seq datasets collected from different genotypes or experimental conditions. Adaptive window sizes are used to correct for differences in signal coverage in near-bait regions, far-cis and trans chromosomes. Using several datasets, we demonstrate that 4C-ker outperforms all existing 4C-Seq pipelines in its ability to reproducibly identify interaction domains at all genomic ranges with different resolution enzymes. 4C-Seq experiments from Igh and Cd83 bait in activated B cells and Tcrb (Eb) bait in double negative T cells and immature B cells. RNA-Seq and ATAC-Seq experiments in DN and Immature B cells.
2016-02-27 | E-GEOD-77645 | biostudies-arrayexpress
Project description:A Preformed Chromatin Architecture Ensures Robust Shh Transcription during Limb Development [4C-seq]
| PRJNA508604 | ENA