A TAD boundary at the HoxD locus segregates opposing limb regulatory landscapes and their target genes
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PROVIDER: PRJNA395249 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The mammalian HoxD cluster is positioned at the boundary between two topologically associating domains (TADs), each of them matching a distinct, enhancer-rich regulatory landscape. During limb development, the telomeric TAD controls the early phase of Hoxd gene transcription in future forearm cells, whereas the centromeric TAD subsequently regulates transcription of more posterior Hoxd genes in presumptive digit cells. The TAD boundary is essential as it prevents the terminal Hoxd13 gene to respond to potent forearm enhancers, thereby allowing the formation of proper proximal limb structures. Here we apply chromosome conformation capture onto embryonic proximal and distal limb bud cells micro-dissected from a set of nested deletions involving part- or all- of this boundary region to try to understand the nature and function of this CTCF- and cohesin-rich DNA region. We document a progressive release of the boundary effect, allowing for inter-TAD contacts to be established, which were favoured by the functional status of the newly accessed enhancers. However, the boundary was highly resilient and only a 400kb large deletion including the whole gene cluster was eventually able to merge the two neighbouring TADs into a single structure. We propose that the whole HoxD cluster is a dynamic transcriptional boundary, showing slight variations depending on both the transcriptional status and the ontogenetic context
2017-12-22 | GSE101715 | GEO
Project description:The mammalian HoxD cluster is positioned at the boundary between two topologically associating domains (TADs), each of them matching a distinct, enhancer-rich regulatory landscape. During limb development, the telomeric TAD controls the early phase of Hoxd gene transcription in future forearm cells, whereas the centromeric TAD subsequently regulates transcription of more posterior Hoxd genes in presumptive digit cells. The TAD boundary is essential as it prevents the terminal Hoxd13 gene to respond to potent forearm enhancers, thereby allowing the formation of proper proximal limb structures. Here we apply chromosome conformation capture onto embryonic proximal and distal limb bud cells micro-dissected from a set of nested deletions involving part- or all- of this boundary region to try to understand the nature and function of this CTCF- and cohesin-rich DNA region. We document a progressive release of the boundary effect, allowing for inter-TAD contacts to be established, which were favoured by the functional status of the newly accessed enhancers. However, the boundary was highly resilient and only a 400kb large deletion including the whole gene cluster was eventually able to merge the two neighbouring TADs into a single structure. We propose that the whole HoxD cluster is a dynamic transcriptional boundary, showing slight variations depending on both the transcriptional status and the ontogenetic context
2017-12-22 | GSE101714 | GEO
Project description:The mammalian HoxD cluster is positioned at the boundary between two topologically associating domains (TADs), each of them matching a distinct, enhancer-rich regulatory landscape. During limb development, the telomeric TAD controls the early phase of Hoxd gene transcription in future forearm cells, whereas the centromeric TAD subsequently regulates transcription of more posterior Hoxd genes in presumptive digit cells. The TAD boundary is essential as it prevents the terminal Hoxd13 gene to respond to potent forearm enhancers, thereby allowing the formation of proper proximal limb structures. Here we apply chromosome conformation capture onto embryonic proximal and distal limb bud cells micro-dissected from a set of nested deletions involving part- or all- of this boundary region to try to understand the nature and function of this CTCF- and cohesin-rich DNA region. We document a progressive release of the boundary effect, allowing for inter-TAD contacts to be established, which were favoured by the functional status of the newly accessed enhancers. However, the boundary was highly resilient and only a 400kb large deletion including the whole gene cluster was eventually able to merge the two neighbouring TADs into a single structure. We propose that the whole HoxD cluster is a dynamic transcriptional boundary, showing slight variations depending on both the transcriptional status and the ontogenetic context
2017-12-22 | GSE101713 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below.
2017-12-22 | GSE101717 | GEO
Project description:Topological associating domains (TADs) are self-interacting genomic units crucial for shaping gene regulation patterns. Despite their importance, the extent of their evolutionary conservation and its functional implications remain largely unknown. In this study, we generate Hi-C and ChIP-seq data and compare TAD organization across four primate and four rodent species, and characterize the genetic and epigenetic properties of TAD boundaries in correspondence to their evolutionary conservation. We find 14% of all human TAD boundaries to be shared among all eight species (ultraconserved), while 15% are human-specific. Ultraconserved TAD boundaries have stronger insulation strength, CTCF binding, and enrichment of older retrotransposons, compared to species-specific boundaries. CRISPR-Cas9 knockouts of two ultraconserved boundaries in mouse models leads to tissue-specific gene expression changes and morphological phenotypes. Deletion of a human-specific boundary near the autism-related AUTS2 gene results in upregulation of this gene in neurons. Overall, our study provides pertinent TAD boundary evolutionary conservation annotations, and showcase the functional importance of TAD evolution.
2023-10-20 | GSE197926 | GEO
Project description:In tetrapods, the HoxD gene cluster is critical for proper limb formation. In the emerging limb buds, different sub-groups of Hoxd genes respond first to a proximal regulatory signal, then to a distal signal that organizes digits. These two regulations emanate from the two TADs flanking HoxD, both containing a range of appropriate enhancer sequences. The telomeric TAD (T-DOM) contains several regulatory elements controlling Hoxd genes, initially in a temporal manner and then in the proximal presumptive forearm. T-DOM is divided into two sub-TADs separated by a CTCF-rich boundary defining two regulatory modules with most limb enhancers concentrated in the more distant module. In order to understand the importance of this regulatory topology to elicit a precise Hoxd gene transcription in time and space, we both deleted or inverted this sub-TAD boundary and eliminated the CTCF binding sites. These perturbations caused a time delay in gene activation, which was subsequently resumed. We then inverted the entire T-DOM to change the respective position of the two sub-TADs, which concomitantly introduced a TAD boundary between HoxD and the inverted T-DOM. This re-arrangement had a stronger impact on the early expression and flattened the Hoxd mRNAs levels. The latter effect was rescued by re-granting access to the enhancers upon deletion of the ectopic boundary. These results highlight the importance of regulatory topologies in the temporal control of gene expression. We also show that, along with time, the affinity of enhancers to find their natural target genes can overcome the presence of both a strong TAD border, and an unfavourable orientation of CTCF sites.
2020-11-10 | GSE154186 | GEO
Project description:ABSTRACT The binding of the transcriptional regulator CTCF to the genome has been implicated in the formation of topologically associated domains (TADs). However, the general mechanisms of folding the genome into TADs are not fully understood. Here, we tested the effects of deleting a CTCF-rich locus on TAD boundary formation. Using genome-wide chromosome conformation capture (Hi-C), we focus on one TAD boundary on chromosome X harboring ~15 CTCF binding sites, and located at the long non-coding RNA (lncRNA) locus Firre. Specifically, this TAD boundary is invariant across evolution, tissues, and temporal dynamics of X-chromosome inactivation. We demonstrate that neither the deletion of this locus, nor the ectopic insertion of Firre cDNA or its ectopic expression are sufficient to alter TADs in a sex-, or allele-specific manner. In contrast, Firre’s deletion disrupts the chromatin super-loop formation of the inactive X-chromosome. Collectively, our findings suggest that apart from CTCF binding, additional mechanisms may play roles in establishing TAD boundary formation. This SuperSeries is composed of the SubSeries listed below.
2018-02-12 | GSE98632 | GEO
Project description:The binding of the transcriptional regulator CTCF to the genome has been implicated in the formation of topologically associated domains (TADs). However, the general mechanisms of folding the genome into TADs are not fully understood. Here, we tested the effects of deleting a CTCF-rich locus on TAD boundary formation. Using genome-wide chromosome conformation capture (Hi-C), we focus on one TAD boundary on chromosome X harboring ~15 CTCF binding sites, and located at the long non-coding RNA (lncRNA) locus Firre. Specifically, this TAD boundary is invariant across evolution, tissues, and temporal dynamics of X-chromosome inactivation. We demonstrate that neither the deletion of this locus, nor the ectopic insertion of Firre cDNA or its ectopic expression are sufficient to alter TADs in a sex-, or allele-specific manner. In contrast, Firre’s deletion disrupts the chromatin super-loop formation of the inactive X-chromosome. Collectively, our findings suggest that apart from CTCF binding, additional mechanisms can play roles in establishing TAD boundary formation.
2018-02-12 | GSE104814 | GEO
Project description:The binding of the transcriptional regulator CTCF to the genome has been implicated in the formation of topologically associated domains (TADs). However, the general mechanisms of folding the genome into TADs are not fully understood. Here, we tested the effects of deleting a CTCF-rich locus on TAD boundary formation. Using genome-wide chromosome conformation capture (Hi-C), we focus on one TAD boundary on chromosome X harboring ~15 CTCF binding sites, and located at the long non-coding RNA (lncRNA) locus Firre. Specifically, this TAD boundary is invariant across evolution, tissues, and temporal dynamics of X-chromosome inactivation. We demonstrate that neither the deletion of this locus, nor the ectopic insertion of Firre cDNA or its ectopic expression are sufficient to alter TADs in a sex-, or allele-specific manner. In contrast, Firre’s deletion disrupts the chromatin super-loop formation of the inactive X-chromosome. Collectively, our findings suggest that apart from CTCF binding, additional mechanisms can play roles in establishing TAD boundary formation.
2018-02-12 | GSE104367 | GEO
Project description:Mammalian genomes are partitioned into sub-megabase to megabase-sized units of preferential interactions called topologically associating domains or TADs, which are likely important for the proper implementation of gene regulatory processes. These domains provide structural scaffolds for distant cis regulatory elements to interact with their target genes within the three-dimensional nuclear space and architectural proteins such as CTCF as well as the cohesin complex participate in the formation of the boundaries between them. However, the importance of the genomic context in providing a given DNA sequence the capacity to act as a boundary element remains to be fully investigated. To address this question, we randomly relocated a topological boundary functionally associated with the mouse HoxD gene cluster and show that it can indeed act similarly outside its initial genomic context. In particular, the relocated DNA segment recruited the required architectural proteins and induced a significant depletion of contacts between genomic regions located across the integration site. The host chromatin landscape was re-organized, with the splitting of the TAD wherein the boundary had integrated. These results provide evidence that topological boundaries can function independently of their site of origin, under physiological conditions during mouse development.
2021-07-05 | GSE166581 | GEO