Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

A cohesin traffic pattern genetically linked to gene regulation [RNA-Seq]

ABSTRACT: Cohesin-mediated loop extrusion folds interphase chromosomes at the ten to hundreds kilobases scale. This process produces structural features such as loops and topologically associating domains. We identify three types of cis-elements that define the chromatin folding landscape generated by loop extrusion. First, CTCF sites form boundaries by stalling extruding cohesin, as shown before. Second, transcription termination sites form boundaries by acting as cohesin unloading sites. RNA polymerase II contributes to boundary formation at transcription termination sites. Third, transcription start sites form boundaries that are mostly independent of cohesin, but are sites where cohesin can pause. Together with cohesin loading at enhancers, and possibly other cis-elements, these loci create a dynamic pattern of cohesin traffic along the genome that guides enhancer-promoter interactions. Disturbing this traffic pattern, by removing CTCF barriers, makes cells sensitive to deletion of genes involved in transcription initiation, such as the SAGA and TFIID complexes, and RNA processing such DEAD-Box RNA helicases. In the absence of CTCF, several of these factors fail to be efficiently recruited to active promoters. We propose that the complex pattern of cohesin movement along chromatin contributes to appropriate promoter-enhancer interactions and localization of transcription and RNA processing factors to active genes.

ORGANISM(S): Homo sapiens

PROVIDER: GSE180713 | GEO | 2022/08/15

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

A cohesin traffic pattern genetically linked to gene regulation [Hi-C]

Project description:Cohesin-mediated loop extrusion folds interphase chromosomes at the ten to hundreds kilobases scale. This process produces structural features such as loops and topologically associating domains. We identify three types of cis-elements that define the chromatin folding landscape generated by loop extrusion. First, CTCF sites form boundaries by stalling extruding cohesin, as shown before. Second, transcription termination sites form boundaries by acting as cohesin unloading sites. RNA polymerase II contributes to boundary formation at transcription termination sites. Third, transcription start sites form boundaries that are mostly independent of cohesin, but are sites where cohesin can pause. Together with cohesin loading at enhancers, and possibly other cis-elements, these loci create a dynamic pattern of cohesin traffic along the genome that guides enhancer-promoter interactions. Disturbing this traffic pattern, by removing CTCF barriers, makes cells sensitive to deletion of genes involved in transcription initiation, such as the SAGA and TFIID complexes, and RNA processing such DEAD-Box RNA helicases. In the absence of CTCF, several of these factors fail to be efficiently recruited to active promoters. We propose that the complex pattern of cohesin movement along chromatin contributes to appropriate promoter-enhancer interactions and localization of transcription and RNA processing factors to active genes.

2022-08-15 | GSE180922 | GEO

A cohesin traffic pattern genetically linked to gene regulation [ChIP-Seq]

2022-08-15 | GSE180690 | GEO

A cohesin traffic pattern genetically linked to gene regulation [CRISPR screens]

Project description:Cohesin-mediated loop extrusion is blocked at specific cis-elements, including CTCF sites, producing patterns of loops and domain boundaries along chromosomes. Here, we explore such cis-elements, and their role in gene regulation. We find that transcription termination sites of active genes form cohesin- and RNA polymerase II-dependent domain boundaries that do not accumulate cohesin. At these sites, cohesin is first stalled and then rapidly unloaded. Start sites of transcriptionally active genes form cohesin-bound boundaries, as shown before, but are cohesin-independent. Together with cohesin loading possibly at enhancers, these sites create a pattern of cohesin traffic that guides enhancer-promoter interactions. Disturbing this traffic pattern, by removing CTCF, renders cells sensitive to knock-out of genes involved in transcription initiation, such as the SAGA complexes, and RNA processing such DEAD/H-Box RNA helicases. Without CTCF, these factors are less efficiently recruited to active promoters.

2022-08-15 | GSE180657 | GEO

Building regulatory landscapes reveals that an enhancer can recruit cohesin to create contact domains, engage CTCF sites and activate distant genes

Project description:Developmental gene expression is often controlled by distal regulatory DNA elements called enhancers. Distant enhancer action is restricted to structural chromosomal domains that are flanked by CTCF-associated boundaries and formed through cohesin chromatin loop extrusion. To better understand how enhancers, genes and CTCF boundaries together form structural domains and control expression, we used a bottom-up approach, building series of active regulatory landscapes in inactive chromatin. We demonstrate here that gene transcription levels and activity over time reduce with increased enhancer distance. The enhancer recruits cohesin to stimulate domain formation and engage flanking CTCF sites in loop formation. It requires cohesin exclusively for the activation of distant genes, not of proximal genes, with nearby CTCF boundaries supporting efficient long-range enhancer action. Our work supports a dual activity model for enhancers: its classic role to stimulate transcription initiation and elongation from target gene promoters and a role to recruit cohesin for the creation of chromosomal domains, the engagement of CTCF sites in chromatin looping, and the activation of distal target genes.

2022-04-08 | GSE180566 | GEO

Cohesin mediates DNA loop extrusion and sister chromatid cohesion by distinct mechanisms [Hi-C]

Project description:Cohesin connects CTCF binding sites and other genomic loci in cis to form chromatin loops, and replicated DNA molecules in trans to mediate sister chromatid cohesion. Whether cohesin uses distinct or related mechanisms to perform these functions is unknown. Here we describe a cohesin hinge mutant, which can extrude DNA into loops but is unable to mediate cohesion. Our results suggest that the latter defect arises during cohesion establishment. The observation that cohesin’s cohesion and loop extrusion activities can be separated indicates that cohesin uses distinct mechanisms to perform these two functions. Unexpectedly, the same hinge mutant can also not be stopped by CTCF boundaries as well as wildtype cohesin. This suggests that cohesion establishment and cohesin’s interaction with CTCF boundaries depend on related mechanisms and raises the possibility that both require transient hinge opening to entrap DNA inside the cohesin ring.

2023-10-25 | GSE235771 | GEO

Cohesin mediates DNA loop extrusion and sister chromatid cohesion by distinct mechanisms [ChIP-seq]

2023-10-25 | GSE235770 | GEO

Interplay between CTCF boundaries and a super enhancer controls cohesin extrusion trajectories and gene expression

Project description:To understand how chromatin domains coordinate gene expression, we dissected select genetic elements organizing topology and transcription around the Prdm14 super enhancer in mouse embryonic stem cells. Taking advantage of allelic polymorphisms, we developed methods to sensitively analyze changes in chromatin topology, gene expression, and protein recruitment. We show that enhancer insulation does not strictly rely on loop formation between its flanking boundaries, that the enhancer activates the Slco5a1 gene beyond its prominent domain boundary, and that it recruits cohesin for loop extrusion. Upon boundary inversion, we find that oppositely-oriented CTCF terminates extrusion trajectories but does not stall cohesin, while deleted or mutated CTCF sites allow cohesin to extend its trajectory. Enhancer-mediated gene activation occurs independent of paused loop extrusion near the gene promoter. We expand upon the loop extrusion model to propose that cohesin loading and extrusion trajectories originating at an enhancer contribute to gene activation.

2021-06-30 | GSE173354 | GEO

MCM complexes are barriers that restrict cohesin-mediated loop extrusion [RNA-Seq]

Project description:Eukaryotic genomes are compacted into loops and topologically associating domains (TADs), which contribute to transcription, recombination and genomic stability. Cohesin extrudes DNA into loops that are thought to lengthen until CTCF boundaries are encountered. Little is known about whether loop extrusion is impeded by DNA-bound machines. Here we show that the minichromosome maintenance (MCM) complex is a barrier that restricts loop extrusion in G1 phase. Single-nucleus Hi-C of mouse zygotes revealed that MCM loading reduces CTCF-anchored loops and decreases TAD boundary insulation, suggesting loop extrusion is impeded before reaching CTCF. This effect extends to HCT116 cells, where MCMs affect the number of CTCF-anchored loops and gene expression. Simulations suggest that MCMs are abundant, randomly positioned, partially permeable barriers. Single-molecule imaging shows that MCMs are physical barriers that frequently constrain cohesin translocation in vitro. Remarkably, chimaeric yeast MCMs harbouring a cohesin-interaction motif from human MCM3 induce cohesin pausing, suggesting that MCMs are “active” barriers with binding sites. These findings raise the possibility that cohesin can arrive by loop extrusion at MCMs, which determine the genomic sites at which sister chromatid cohesion is established. Based on in vivo, in silico and in vitro data, we conclude that distinct loop extrusion barriers shape the 3D genome.

2022-03-08 | GSE196496 | GEO

Cohesin-dependent chromosome loop extrusion is limited by transcription and stalled replication forks [RNA-seq]

Project description:Genome function depends on regulated chromosome folding, and loop extrusion by the protein complex cohesin is essential for this multilayered organization. The chromosomal positioning of cohesin is controlled by transcription, and the complex also localizes to stalled replication forks. However, the role of transcription and replication in chromosome looping remains unclear. Here, we show that reduction of chromosome-bound RNA polymerase weakens normal cohesin loop extrusion boundaries, allowing cohesin to form new long-range chromosome cis interactions. Stress response genes activated by transcription inhibition are also shown to act as new loop extrusion boundaries. Furthermore, cohesin loop extrusion during early S-phase is jointly controlled by transcription and replication units. Together, the results reveal that replication and transcription machineries are chromosome folding regulators that block the progression of loop-extruding cohesin, opening for new perspectives on cohesin’s roles in genome function and stability.

2022-06-15 | GSE191207 | GEO

Cohesin-dependent chromosome loop extrusion is limited by transcription and stalled replication forks [Hi-C]

2022-06-15 | GSE162193 | GEO