Developmentally regulated Shh expression is robust to TAD perturbations
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE135840 | GEO | 2019/08/15
REPOSITORIES: GEO
Similar Datasets
Project description:Limb-specific expression of Shh is regulated by the long-range (~one megabasepair distant) ZRS enhancer. In the mouse, murine limb bud restricted spatiotemporal expression of Shh occurs from ~E10 until E11.5 at the distal posterior margin is essential for the correct formation of the autopod. Here, we have analyzed the higher-order chromatin conformation of Shh in expressing and non-expressing tissues, both by fluorescence in situ hybridization (FISH) and by chromosome conformation capture (5C). Conventional and super-resolution light microscopy identified significantly elevated frequences of Shh/ZRS co-localization only in the Shh expressing regions of the limb bud consistent with the formation of an enhancer-promoter loop. However, Shh-ZRS spatial distances were consistently shorter than intervening distances to a neural enhancer in all tissues and developmental stages analyzed – regardless of Shh expression. 5C also identified a topologically associating domain (TAD) over the Shh-ZRS genomic region and enriched interactions between Shh and ZRS, but in the head, body and limb buds of E11.5 embryos, so also not linked to Shh expression. We show that gene-enhancer (Shh/ZRS) co-localization correlates with the spatiotemporal domain of limb bud-specific Shh expression, but that close Shh/ZRS proximity in the nucleus occurs regardless of whether the gene or enhancer is active. We suggest that this constrained chromatin configuration optimises the opportunity for the active enhancer to locate and instigate Shh expression.
2016-05-03 | GSE79947 | GEO
Project description:Enhancers can regulate their target promoters over large genomic distances for which spatial proximity between these elements is assumed to be necessary. Topologically Associating Domains (TADs) are thought to provide such a spatial environment for regulatory domains harboring multiple enhancers driving complex expression of developmental genes. However, how enhancer position within the TAD affects its function in vivo is not known. Here, we address this question by generating a series of genome-engineered mouse lines in which we systematically reposition the limb enhancer of Sonic hedgehog (Shh), ZRS, to various positions within and outside of its TAD to analyze positional effects on gene expression, chromatin folding, and limb phenotype. We find that the enhancer activates Shh only when located within the same TAD, however, its activity varies across intra-TAD positions. ZRS-driven Shh expression drops rapidly with increasing distance from the promoter but eventually plateaus irrespective of linear distance. Moreover, engineering of 3D enhancer-promoter contacts through integration of different CTCF sites reveals that increased contact frequencies do not directly translate into increased transcriptional output and may cause undesired consequences in vivo due to detrimental effects on Shh expression in other tissues. Finally, we show a selective ability of the ZRS enhancer to activate non-target genes in ectopic TADs. Our work highlights the importance of genomic context within TADs for enhancer function and our limited understanding of the interplay between regulatory sequences within these domains.
2023-08-01 | GSE223757 | GEO
Project description:Expression of Shh in the limb is dependent on a distant enhancer located 850kb away from the gene promoter. We performed chromatin conformation capture (4C-Seq) analysis of the Shh locus in E11.5 mouse limbs so as to better understand the relationship between this regulatory interaction and the structural organisation of the locus. The experiments were performed on wild-type animals as well as on animals carrying an engineered chromosomal inversion (INV(6-C2) (INV6)) . The different viewpoints used (Shh, ZRS, Nom1, Rbm33, Rnf32) enable to characterize the 3D organisation of the locus in the different contexts. The inversion INV6 disrupts the normal topological organisation of the Shh locus in a compact 3D-domain and prevents the physical and regulatory interaction between Shh and its limb enhancer, even though the genomic distance separating the two elements is reduced compared to WT.
2017-01-12 | E-MTAB-4980 | biostudies-arrayexpress
Project description:The expression of genes with a key function during development is frequently controlled by large regulatory landscapes containing multiple enhancer elements. These landscapes often match Topologically Associating Domains (TADs) and sometimes integrate range of similar enhancers, thus leading to TADs having a global regulatory specificity. To assess the relative functional importance of enhancer sequences versus the regulatory domain they are included in, we set out to transfer one particular enhancer sequence from its native domain into a TAD with a closely related, yet different functional specificity. We used Hoxd genes and their biphasic regulation during limb development as a paradigm, since they are first activated in proximal limb cells by enhancers located in one TAD, which is then silenced at the time when the neighboring TAD starts to activate its enhancers in distal limb cells. We introduced a strong distal limb enhancer into the ‘proximal limb TAD’ and found that its new context strongly suppresses its distal specificity, even though it continues to be bound by HOX13 transcription factors, which normally are responsible for this activity. Using local genetic alterations and chromatin conformation measurements, we see that the enhancer is capable of interacting with target genes, with a pattern comparable to its adoptive neighborhood of enhancers. Its activity in distal limb cells can be rescued only when a large portion of the surrounding environment is removed. These results indicate that, at least in some cases, the functioning of enhancer elements is subordinated to the local chromatin context, which can exert a dominant control over its activity.
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Project description:The expression of genes with a key function during development is frequently controlled by large regulatory landscapes containing multiple enhancer elements. These landscapes often match Topologically Associating Domains (TADs) and sometimes integrate range of similar enhancers, thus leading to TADs having a global regulatory specificity. To assess the relative functional importance of enhancer sequences versus the regulatory domain they are included in, we set out to transfer one particular enhancer sequence from its native domain into a TAD with a closely related, yet different functional specificity. We used Hoxd genes and their biphasic regulation during limb development as a paradigm, since they are first activated in proximal limb cells by enhancers located in one TAD, which is then silenced at the time when the neighboring TAD starts to activate its enhancers in distal limb cells. We introduced a strong distal limb enhancer into the ‘proximal limb TAD’ and found that its new context strongly suppresses its distal specificity, even though it continues to be bound by HOX13 transcription factors, which normally are responsible for this activity. Using local genetic alterations and chromatin conformation measurements, we see that the enhancer is capable of interacting with target genes, with a pattern comparable to its adoptive neighborhood of enhancers. Its activity in distal limb cells can be rescued only when a large portion of the surrounding environment is removed. These results indicate that, at least in some cases, the functioning of enhancer elements is subordinated to the local chromatin context, which can exert a dominant control over its activity.
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Project description:The expression of genes with a key function during development is frequently controlled by large regulatory landscapes containing multiple enhancer elements. These landscapes often match Topologically Associating Domains (TADs) and sometimes integrate range of similar enhancers, thus leading to TADs having a global regulatory specificity. To assess the relative functional importance of enhancer sequences versus the regulatory domain they are included in, we set out to transfer one particular enhancer sequence from its native domain into a TAD with a closely related, yet different functional specificity. We used Hoxd genes and their biphasic regulation during limb development as a paradigm, since they are first activated in proximal limb cells by enhancers located in one TAD, which is then silenced at the time when the neighboring TAD starts to activate its enhancers in distal limb cells. We introduced a strong distal limb enhancer into the ‘proximal limb TAD’ and found that its new context strongly suppresses its distal specificity, even though it continues to be bound by HOX13 transcription factors, which normally are responsible for this activity. Using local genetic alterations and chromatin conformation measurements, we see that the enhancer is capable of interacting with target genes, with a pattern comparable to its adoptive neighborhood of enhancers. Its activity in distal limb cells can be rescued only when a large portion of the surrounding environment is removed. These results indicate that, at least in some cases, the functioning of enhancer elements is subordinated to the local chromatin context, which can exert a dominant control over its activity.
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Project description:The expression of genes with a key function during development is frequently controlled by large regulatory landscapes containing multiple enhancer elements. These landscapes often match Topologically Associating Domains (TADs) and sometimes integrate range of similar enhancers, thus leading to TADs having a global regulatory specificity. To assess the relative functional importance of enhancer sequences versus the regulatory domain they are included in, we set out to transfer one particular enhancer sequence from its native domain into a TAD with a closely related, yet different functional specificity. We used Hoxd genes and their biphasic regulation during limb development as a paradigm, since they are first activated in proximal limb cells by enhancers located in one TAD, which is then silenced at the time when the neighboring TAD starts to activate its enhancers in distal limb cells. We introduced a strong distal limb enhancer into the ‘proximal limb TAD’ and found that its new context strongly suppresses its distal specificity, even though it continues to be bound by HOX13 transcription factors, which normally are responsible for this activity. Using local genetic alterations and chromatin conformation measurements, we see that the enhancer is capable of interacting with target genes, with a pattern comparable to its adoptive neighborhood of enhancers. Its activity in distal limb cells can be rescued only when a large portion of the surrounding environment is removed. These results indicate that, at least in some cases, the functioning of enhancer elements is subordinated to the local chromatin context, which can exert a dominant control over its activity.
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Project description:The expression of genes with a key function during development is frequently controlled by large regulatory landscapes containing multiple enhancer elements. These landscapes often match Topologically Associating Domains (TADs) and sometimes integrate range of similar enhancers, thus leading to TADs having a global regulatory specificity. To assess the relative functional importance of enhancer sequences versus the regulatory domain they are included in, we set out to transfer one particular enhancer sequence from its native domain into a TAD with a closely related, yet different functional specificity. We used Hoxd genes and their biphasic regulation during limb development as a paradigm, since they are first activated in proximal limb cells by enhancers located in one TAD, which is then silenced at the time when the neighboring TAD starts to activate its enhancers in distal limb cells. We introduced a strong distal limb enhancer into the ‘proximal limb TAD’ and found that its new context strongly suppresses its distal specificity, even though it continues to be bound by HOX13 transcription factors, which normally are responsible for this activity. Using local genetic alterations and chromatin conformation measurements, we see that the enhancer is capable of interacting with target genes, with a pattern comparable to its adoptive neighborhood of enhancers. Its activity in distal limb cells can be rescued only when a large portion of the surrounding environment is removed. These results indicate that, at least in some cases, the functioning of enhancer elements is subordinated to the local chromatin context, which can exert a dominant control over its activity.
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