Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Facultative CTCF sites moderate mammary super-enhancer activity and regulate juxtaposed gene in non-mammary cells [RNA-seq]

ABSTRACT: Precise spatiotemporal regulation of genetic programs, driven by cellspecific super-enhancers, is paramount for the function of cell lineages. Studies have suggested that insulated neighborhoods, formed by the zincfinger protein CTCF, sequester genes and their associated enhancers thus preventing them from trespassing on off-target genes. Although this could explain the enhancer-gene-specificity conundrum, there is limited genetic evidence that the search space of cell-specific super-enhancers is constrained by CTCF. We have addressed this question in the Wap locus with its exceptional mammary-specific super-enhancer, which is separated by five CTCF sites from neighboring genes. Three of these sites are positioned between the Wap super-enhancer and the widely expressed Ramp3. Enhancer deletions demonstrated that the Wap super-enhancer controls Ramp3 expression despite the presence of three parting CTCF sites. Individual and combinatorial deletions of these CTCF sites revealed cell-specific functions of the conserved anchor site. Although unable to block super-enhancer activity, it muffled its impact on Ramp3 in mammary tissue. Unexpectedly, this CTCF site was obligatory for Ramp3 expression in cerebellum, suggesting the coinciding presence of regulatory elements. While our results suggest a surprisingly limited in vivo role for a CTCF anchor in blocking a mammary-specific super-enhancer, they also implicate this site in cerebellum-specific gene activation. Our study illustrates additional complexities of CTCF sites supporting tissue-specific functions.

ORGANISM(S): Mus musculus

PROVIDER: GSE92931 | GEO | 2017/05/25

SECONDARY ACCESSION(S): PRJNA359105

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Facultative CTCF sites moderate mammary super-enhancer activity and regulate juxtaposed gene in non-mammary cells [ChIP-seq]

Project description:Precise spatiotemporal regulation of genetic programs, driven by cellspecific super-enhancers, is paramount for the function of cell lineages. Studies have suggested that insulated neighborhoods, formed by the zincfinger protein CTCF, sequester genes and their associated enhancers thus preventing them from trespassing on off-target genes. Although this could explain the enhancer-gene-specificity conundrum, there is limited genetic evidence that the search space of cell-specific super-enhancers is constrained by CTCF. We have addressed this question in the Wap locus with its exceptional mammary-specific super-enhancer, which is separated by five CTCF sites from neighboring genes. Three of these sites are positioned between the Wap super-enhancer and the widely expressed Ramp3. Enhancer deletions demonstrated that the Wap super-enhancer controls Ramp3 expression despite the presence of three parting CTCF sites. Individual and combinatorial deletions of these CTCF sites revealed cell-specific functions of the conserved anchor site. Although unable to block super-enhancer activity, it muffled its impact on Ramp3 in mammary tissue. Unexpectedly, this CTCF site was obligatory for Ramp3 expression in cerebellum, suggesting the coinciding presence of regulatory elements. While our results suggest a surprisingly limited in vivo role for a CTCF anchor in blocking a mammary-specific super-enhancer, they also implicate this site in cerebellum-specific gene activation. Our study illustrates additional complexities of CTCF sites supporting tissue-specific functions.

2017-05-25 | GSE92587 | GEO

Facultative CTCF sites moderate mammary super-enhancer activity and regulate juxtaposed gene in non-mammary cells [4C-seq]

2017-05-25 | GSE97803 | GEO

Progressing enhancer landscape during mammary differentiation controls gene regulation [ChIP-seq]

Project description:The mammary luminal lineage relies on the common cytokine-sensing transcription factor STAT5 to establish super-enhancers during pregnancy and activate mammary genes required for the nutrition of the offspring. Exploiting progressive differentiation during lactation, we investigated how hormonal cues shape an evolving enhancer landscape and impact the biology of mammary cells. Employing ChIP-seq, we uncover a changing transcription factor occupancy at mammary enhancers. Using mouse genetics, we demonstrate changing biological properties of enhancers as lactation progresses, with individual enhancers gaining strength and an abolished need for the Wap seed enhancer. We further investigated whether permissive chromatin facilitates cell-specific transcription factor binding. Wap enhancers translocated into the widely expressed neighboring Ramp3 gene retained their mammary-specificity and failed to activate the receptive Ramp3 gene in non-mammary tissues. Our studies unveil a previously unrecognized progressive enhancer landscape, in which structurally equivalent components serve unique and differentiation-specific functions. While enhancer redundancy has been suggested and demonstrated for many genes, components of the cytokine-responsive mammary tripartite Wap super-enhancer display a remarkable specificity.

2018-09-18 | GSE115368 | GEO

Progressing enhancer landscape during mammary differentiation controls gene regulation [RNA-seq]

2018-09-18 | GSE115369 | GEO

Hierarchy within the mammary STAT5-driven Wap super-enhancer

Project description:Super-enhancers comprise of dense transcription factor platforms highly enriched for active chromatin marks. A paucity of functional data led us to investigate their role in the mammary gland, an organ characterized by exceptional gene regulatory dynamics during pregnancy. ChIP-Seq for the master regulator STAT5, the glucocorticoid receptor, H3K27ac and MED1, identified 440 mammary-specific super-enhancers, half of which were associated with genes activated during pregnancy. We interrogated the Wap super-enhancer, generating mice carrying mutations in STAT5 binding sites within its three constituent enhancers. Individually, only the most distal site displayed significant enhancer activity. However, combinatorial mutations showed that the 1,000-fold gene induction relied on all enhancers. Disabling the binding sites of STAT5, NFIB and ELF5 in the proximal enhancer incapacitated the entire super-enhancer, suggesting an enhancer hierarchy. The identification of mammary-specific super-enhancers and the mechanistic exploration of the Wap locus provide insight into the complexity of cell-specific and hormone-regulated genes. ChIP-Seq for STAT5A, GR, H3K27ac, MED1, NFIB, ELF5, RNA Pol II, and H3K4me3 in wild type (WT) mammary tissues at day one of lactation (L1), and ChIP-Seq for STAT5A, GR, H3K27ac, MED1, NFIB, ELF5, and H3K4me3 in WT mammary tissues at day 13 of pregnancy (p13). ChIP-Seq for STAT5A, GR, H3K27a in Wap-delE1a, -delE1b, -delE1c, -delE2 and -delE3 mutant mammary tissues at L1, and ChIP-Seq for NFIB and ELF5 in Wap-delE1b and -delE1c mutant mammary tissues at L1. ChIP-Seq for H3K4me3 in mammary-epthelial cells at p13 and L1. DNase-seq in WT mammary tissues at L1 and DNase-seq in Wap-delE1a, -delE1c, and -delE3 mutant mammary tissues at L1.

2016-05-31 | E-GEOD-74826 | biostudies-arrayexpress

Hierarchy within the mammary STAT5-driven Wap super-enhancer

2016-05-31 | GSE74826 | GEO

Interdependence of a mammary-specific super-enhancer and its native promoter facilitates gene activation during pregnancy

Project description:Lineage-specific genetic programs rely on cell-restricted super-enhancers, platforms for high-density occupation by transcription factors. It is not known whether super-enhancers synergize specifically with their native promoters or provide autonomous regulatory platforms. Here we investigate the ability of the mammary Wap super-enhancer to activate the promoter of the juxtaposed and ubiquitously expressed Tbrg4 gene in the mouse mammary gland. The Wap super-enhancer was fused, by itself or in combination with its promoter, with the Tbrg4 gene. While the Wap super-enhancer activated the Tbrg4 promoter five-fold, the combination of Wap super-enhancer and promoter resulted in an 80-fold gene activation, demonstrating lineage-specific promoter-enhancer synergy. Employing ChIP-seq profiling, we uncover a chromatin platform permissive for high level expression that develops in the native promoter-enhancer context but not with a heterologous promoter. Post-transcriptional mechanisms through the Wap 3’UTR have been proposed to account for the exceptional high mRNA levels during lactation, but our mouse genetic experiments failed to support this. Lastly, we discovered that the CREB transcription factor is an integral part of the Tbrg4 promoter but not essential for its function. Taken together, our data reveal that lineage-specific enhancer-promoter synergy is critical for mammary gene regulation during pregnancy and lactation.

2020-03-24 | GSE145193 | GEO

Functional analysis of CTCF sites associated with cytokine-sensing mammary-specific enhancers in the complex casein locus [ChIP-seq]

Project description:The zinc finger protein CTCF has been invoked in establishing functional boundaries between genes and thereby controlling enhancer activities. However, there is limited genetic evidence to support such a concept. We have now addressed this question in a locus containing five mammary-specific genes controlled by enhancers. We have identified four CTCF binding sites in the casein locus, two at the outside boundaries and two associated with a super-enhancer. Individual deletions of these sites from the mouse genome did not alter expression of the five casein genes and Odam. However, deletion of the border CTCF site separating the Csn1s1 enhancer from non-mammary genes resulted in the activation of Sult1d1 at a distance of more than 95 kb but not the more proximal Sult1e1 gene. Loss of this CTCF site led to de novo interactions between the Csn1s1 enhancer and the Sult1d1 promoter but not with the silent Sult1e1 gene. Our study suggests that most CTCF sites associated with cell-specific enhancers and super-enhancers have no measurable in vivo activity. Only the loss of one CTCF site led to the induction of a juxtaposed active non-target promoter. Our study also demonstrated that cell-specific enhancers are unable to activate juxtaposed silent non-target promoters.

2017-03-24 | GSE92591 | GEO

Chromosome loop control of oncogenic MYC produces a common vulnerability in diverse cancers [HiChIP]

Project description:The majority of human cancers become highly dependent on a deregulated MYC oncogene, thus identifying a common mechanism underlying MYC regulation could provide valuable targets for therapy. We show here that diverse tumor-specific super-enhancers acquired throughout the 3Mb MYC insulated neighborhood functionally interact with a single conserved site occupied by CTCF protein in the MYC promoter. CRISPR-mediated deletion analysis shows that this common CTCF site is required for super-enhancer looping to the MYC promoter, high MYC expression and rapid cell proliferation in multiple cancers. Targeted methylation of the MYC enhancer anchor by a dCAS9-DNMT3A-3L fusion protein abrogates CTCF binding with consequent loss of MYC expression, suggesting a common vulnerability and a novel approach for therapeutic targeting of aggressive cancers.

2018-03-20 | GSE112000 | GEO

Chromosome loop control of oncogenic MYC produces a common vulnerability in diverse cancers [4C-seq]

2016-12-24 | GSE92880 | GEO