Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The role of insulators and transcription in 3D chromatin organisation of flies

ABSTRACT: The DNA in humans and many animals is compartmentalised in topologically associating domains (TADs). In Drosophila, several architectural proteins are enriched at TAD borders, but we are still missing evidence that these proteins have a functional role in TAD maintenance. Here, we show that depletion of BEAF-32, Cp190 and Chro leads to changes in TAD organisation and chromatin loops. Their depletion affects mainly TAD borders in heterochromatin, while euchromatin TAD borders are resilient to these mutants. Furthermore, transcriptomic data identified thousands of genes displaying differential expression in these mutants and that majority of differentially expressed genes are in TADs that are reorganised. In contrast, we observed a lower effect on gene expression by the loss of chromatin loops. Our work identified for the first time a functional role for architectural proteins at TAD borders in Drosophila and a strong link between TAD reorganisation and changes in gene expression.

ORGANISM(S): Drosophila melanogaster

PROVIDER: GSE147059 | GEO | 2022/02/07

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Widespread rearrangement of 3D chromatin organization underlies Polycomb-mediated stress-induced silencing [ChIP]

Project description:Chromosomes of metazoan organisms are partitioned in the interphase nucleus into discrete topologically associating domains (TADs). Borders between TADs are preferentially formed in regions containing high density of active genes and clusters of architectural protein binding sites. Transcription of most genes is turned off during the heat shock response in Drosophila. Here we show that temperature stress induces relocalization of architectural proteins from TAD borders to inside TADs, and this is accompanied by a dramatic rearrangement in the 3D organization of the nucleus. TAD border strength declines, allowing for an increase in long-distance inter-TAD interactions. Similar but quantitatively weaker effects are observed upon inhibition of transcription or depletion of individual architectural proteins. New heat shock-induced inter-TAD interactions result in increased contacts among enhancers and promoters of silenced genes, which recruit Pc and form Pc bodies at the nucleolus. These results suggest that the TAD organization of metazoan genomes is plastic and can be quickly reconfigured to allow new interactions between distant sequences. Analysis of the distribution of architectural proteins, chromatin proteins and histone modifications in Drosophila Kc167 cells. Cells were grown at 25 C (NT) or heat shocked for 20 min at 36.5 C (HS). Both control and reference samples are included. For some of the samples, replicates are also included.

2015-02-24 | E-GEOD-62904 | biostudies-arrayexpress

Widespread rearrangement of 3D chromatin organization underlies Polycomb-mediated stress-induced silencing [Hi-C]

Project description:Chromosomes of metazoan organisms are partitioned in the interphase nucleus into discrete topologically associating domains (TADs). Borders between TADs are preferentially formed in regions containing high density of active genes and clusters of architectural protein binding sites. Transcription of most genes is turned off during the heat shock response in Drosophila. Here we show that temperature stress induces relocalization of architectural proteins from TAD borders to inside TADs, and this is accompanied by a dramatic rearrangement in the 3D organization of the nucleus. TAD border strength declines, allowing for an increase in long-distance inter-TAD interactions. Similar but quantitatively weaker effects are observed upon inhibition of transcription or depletion of individual architectural proteins. New heat shock-induced inter-TAD interactions result in increased contacts among enhancers and promoters of silenced genes, which recruit Pc and form Pc bodies at the nucleolus. These results suggest that the TAD organization of metazoan genomes is plastic and can be quickly reconfigured to allow new interactions between distant sequences. Analysis of 3D chromatin organization using Hi-C in Drosophila Kc167 cells. Cells were grown at 25 C and heat shocked for 20 min at 36.5 C. Cells were also treated with flavopiridol or triptolide to inhibit transcription elongation or initiation, respectively. Cells were depeleted of Cap-H2 or Rad21 using RNAi. Finally, cells depleted of RAd21 were subjected to heat shock at 36.5 C for 20 min.

2015-02-24 | E-GEOD-63515 | biostudies-arrayexpress

Widespread rearrangement of 3D chromatin organization underlies Polycomb-mediated stress-induced silencing [Hi-C]

2015-02-24 | GSE63515 | GEO

Widespread rearrangement of 3D chromatin organization underlies Polycomb-mediated stress-induced silencing [ChIP]

2015-02-24 | GSE62904 | GEO

Sub-kb resolution Hi-C in D. melanogaster reveals conserved characteristics of TADs between insect and mammalian cells

Project description:Topologically associating domains (TADs) are widely recognized as fundamental elements of the 3D structure of the eukaryotic genome. However, while the structural importance of the insulator protein CTCF together with cohesin at TAD borders in mammalian cells is well established, the absence of such co-localization at most TAD borders in recent Hi-C studies of D. melanogaster is enigmatic, raising the possibility that these TAD border elements are not generally conserved among metazoans. Using in situ Hi-C with sub-kb resolution, we show that the genome of D. melanogaster is almost completely partitioned into more than 4,000 TADs (median size, 13 kb), nearly 7-fold more than previously identified. The overwhelming majority of these TADs are demarcated by pairs of Drosophila-specific insulator proteins, BEAF-32/CP190 or BEAF-32/Chromator, indicating that these proteins may play an analogous role in Drosophila as that of the CTCF/cohesin pair in mammals. Moreover, we find that previously identified TADs enriched for inactive chromatin are predominantly assembled from the higher-level interactions between smaller TADs. In contrast, the closely-spaced small TADs in regions previously thought to be unstructured “inter-TADs” are organized in an open configuration with far fewer TAD-TAD interactions. Such structures can also be identified in some “inter-TAD” regions of the mammalian genome, suggesting that larger assemblages of small self-interacting TADs separated by a “burst” of adjacent small, weakly interacting TADs may be a conserved, basic characteristic of the higher order folding of the metazoan genome.

2017-11-22 | GSE101317 | GEO

Chromatin architecture reorganisation during neuronal cell differentiation in Drosophila genome

Project description:Compartmentalisation of the genome as topologically associating domains (TADs) may have a regulatory role in development and cellular functioning, but the mechanism involved in TAD establishment is still unclear. Here, we present the first high-resolution contact map of Drosophila melanogaster neuronal cells (BG3) and identify different classes of TADs by comparing this to genome organisation in embryonic cells (Kc167). We find new interactions during differentiation in neuronal cells, which are reflected as enhanced long-range interactions. This is supported by pronounced enrichment of CTCF at TAD borders. Furthermore, we observed strong divergent transcription, together with RNA Polymerase II occupancy, and an increase in DNA accessibility at the TAD borders. Interestingly, TAD borders that are specific to neuronal cells are enriched in enhancers controlled by neuronal specific transcription factors. Our results suggest that TADs are dynamic across developmental stages and reflect the interplay between insulators, transcriptional states and enhancer activities.

2019-01-18 | GSE122603 | GEO

KSHV Topologically Associating Domains in Latent Chromatin and Regulation of Reactivation

Project description:Eukaryotic genomes are structurally organized via the formation of multiple loops that create gene expression regulatory units called topologically associating domains (TADs). Here we revealed the KSHV TAD structure at 500 base pair resolution and constructed a 3D KSHV genomic structural model. The latent KSHV genome formed very similar TAD structures among three different naturally infected PEL cell lines. When KSHV reactivation was triggered, genomic loops within TADs were dramatically decreased, while contacts extending outside of TAD borders increased, leading to formation of a larger regulatory unit with a shift from repressive to active compartments (B to A). The 3D structural model proposes that the immediate-early promoter region is localized on the periphery of the 3D viral genome, while highly inducible non-coding RNA regions moved toward the inner space of the structure, resembling the coordination of a "bird cage" during reactivation. Finally, inhibition of the initial burst of lytic gene expression by stop codon insertion in the viral transactivator reduced genomic loops, while supplementing K-Rta expression in trans during establishment of latency attenuated the defect. Our studies suggest that the latent 3D genomic structural information is embedded in the lytic gene transcription program.

2022-06-25 | GSE163696 | GEO

Active chromatin and transcription play a key role in chromosome partitioning into topologiÑ?ally associating domains

Project description:Recent advances enabled by Hi-C technique have unraveled principles of chromosomal folding, which were since linked to many genomic processes. In particular, Hi-C revealed that chromosomes of animals are organized into Topologically Associating Domains (TADs), evolutionary conserved compact chromatin domains that influence gene expression. However, mechanisms that underlie partitioning of the genome into TADs remain poorly understood. To explore principals of TAD folding in Drosophila melanogaster, we performed Hi-C and PolyA+ RNA-seq in four cell lines of various origins (S2, Kc167, DmBG3-c2, and OSC). Contrary to previous studies, we find that regions between TADs (i.e. the inter-TADs and TAD boundaries) in Drosophila are only weakly enriched with the insulator protein dCTCF, while another insulator protein Su(Hw) is preferentially present within TADs. However, Drosophila inter-TADs harbor active chromatin and constitutively transcribed (housekeeping) genes. Accordingly, we find that binding of insulator proteins dCTCF and Su(Hw) predict TAD boundaries much worse than the active chromatin marks (in the minimal case, H3K4me3 and total RNA) do. Moreover, inter-TADs correspond to decompacted interbands of polytene chromosomes, whereas TADs mostly correspond to densely packed bands. Collectively, our results suggest that TADs are condensed chromatin domains depleted in active chromatin marks, separated by regions of active chromatin that cannot be organized into compact structures, possibly due to high levels of histone acetylation. Finally, we test this hypothesis by polymer simulations, and find that TAD partitioning can be explained by different modes of inter-nucleosomal interactions for active and inactive chromatin. Hi-C experiments, PolyA+ RNA profiling and mapping of chromosomal rearrangements in four Drosophila melanogaster cell lines.

2015-10-26 | E-GEOD-69013 | biostudies-arrayexpress

M1BP cooperates with CP190 to activate transcription at TAD borders and promote chromatin insulator activity

Project description:Genome organization is driven by forces affecting transcriptional state, but the relationship between transcription and genome architecture remains unclear. Here, we identified the Drosophila transcription factor Motif 1 Binding Protein (M1BP) in physical association with the gypsy chromatin insulator core complex, including the universal insulator protein CP190. M1BP is required for enhancer-blocking and barrier activities of the gypsy insulator as well as its proper nuclear localization. Genome-wide, M1BP specifically colocalizes with CP190 at Motif 1-containing promoters, which are enriched at topologically associating domain (TAD) borders. M1BP facilitates CP190 chromatin binding at many shared sites and vice versa. Both factors promote Motif 1-dependent gene expression and transcription near TAD borders genome-wide. Finally, loss of M1BP reduces chromatin accessibility and increases both inter- and intra-TAD local genome compaction. Our results reveal physical and functional interaction between CP190 and M1BP to activate transcription at TAD borders and mediate chromatin insulator-dependent genome organization.

2021-06-07 | PXD026497 | Pride

SRF is a new player in 3D genome organization and stem cell pluripotency

Project description:Serum response factor (SRF) is a transcription factor essential for cell proliferation, differentiation, and migration, and is required for primitive streak and mesoderm formation in the embryo. The canonical roles of SRF are mediated by a diverse set of context-dependent cofactors. Here we show that SRF physically interacts with CTCF and cohesin subunits at TAD boundaries and loop anchors. SRF reinforces the insulation of TADs and promotes the formation of long-range chromatin loops. In ES cells, SRF associates with Oct4, Sox2, and Nanog and contributes to the formation of 3D pluripotency hubs. Our findings reveal new roles of SRF in higher-order chromatin organization.

2024-10-14 | PXD049365 | Pride

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data