Similar Datasets
Project description:The HoxD gene cluster is critical for proper limb formation in tetrapods. In the emerging limb buds, different subgroups of Hoxd genes respond first to a proximal regulatory signal, then to a distal signal that organizes digits. These two regulations are exclusive from one another and emanate from two distinct topologically associating domains (TADs) flanking HoxD, both containing a range of appropriate enhancer sequences. The telomeric TAD (T-DOM) contains several enhancers active in presumptive forearm cells and is divided into two sub-TADs separated by a CTCF-rich boundary, which defines two regulatory submodules. To understand the importance of this particular regulatory topology to control Hoxd gene transcription in time and space, we either deleted or inverted this sub-TAD boundary, eliminated the CTCF binding sites, or inverted the entire T-DOM to exchange the respective positions of the two sub-TADs. The effects of such perturbations on the transcriptional regulation of Hoxd genes illustrate the requirement of this regulatory topology for the precise timing of gene activation. However, the spatial distribution of transcripts was eventually resumed, showing that the presence of enhancer sequences, rather than either their exact topology or a particular chromatin architecture, is the key factor. We also show that the affinity of enhancers to find their natural target genes can overcome the presence of both a strong TAD border and an unfavorable orientation of CTCF sites.
| S-EPMC7733857 | biostudies-literature
Project description:The HoxD gene cluster is critical for proper limb formation in tetrapods. 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 are exclusive from one another and emanate separately from two TADs flanking HoxD, both containing a range of appropriate enhancer sequences. The telomeric TAD (T-DOM) contains several enhancers active in presumptive forearm cells and is divided into two sub-TADs separated by a CTCF-rich boundary, which defines two regulatory sub-modules. To understand the importance of this particular regulatory topology to control Hoxd gene transcription in time and space, we either deleted or inverted this sub-TAD boundary, eliminated the CTCF binding sites or inverted the entire T-DOM to exchange the respective positions of the two sub-TADs. The effects of such perturbations on the transcriptional regulation of Hoxd genes illustrates the requirement of this regulatory topology for the precise timing of gene activation. However, the spatial distribution of transcripts is eventually resumed, showing that the presence of enhancers sequences, rather than either their exact topology or a particular chromatin architecture, is the key factor. We also show that 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 | GSE154188 | GEO
Project description:The HoxD gene cluster is critical for proper limb formation in tetrapods. 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 are exclusive from one another and emanate separately from two TADs flanking HoxD, both containing a range of appropriate enhancer sequences. The telomeric TAD (T-DOM) contains several enhancers active in presumptive forearm cells and is divided into two sub-TADs separated by a CTCF-rich boundary, which defines two regulatory sub-modules. To understand the importance of this particular regulatory topology to control Hoxd gene transcription in time and space, we either deleted or inverted this sub-TAD boundary, eliminated the CTCF binding sites or inverted the entire T-DOM to exchange the respective positions of the two sub-TADs. The effects of such perturbations on the transcriptional regulation of Hoxd genes illustrates the requirement of this regulatory topology for the precise timing of gene activation. However, the spatial distribution of transcripts is eventually resumed, showing that the presence of enhancers sequences, rather than either their exact topology or a particular chromatin architecture, is the key factor. We also show that 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 | GSE154187 | 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:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2013-10-23 | E-GEOD-45242 | biostudies-arrayexpress
Project description:Chromatin topology and the timing of enhancer function at the HoxD locus
| PRJNA645387 | ENA
Project description:This SuperSeries is composed of the SubSeries listed below.
2013-10-23 | GSE45242 | GEO
Project description:Chromatin topology and the timing of enhancer function at the HoxD locus [RNA-seq]
| PRJNA645390 | ENA
Project description:Chromatin topology and the timing of enhancer function at the HoxD locus [4C-seq]
| PRJNA645388 | ENA
Project description:Chromatin topology and the timing of enhancer function at the HoxD locus [ChIP-seq]
| PRJNA645389 | ENA