Cohesin is positioned in mammalian genomes by transcription, CTCF and Wapl
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE76303 | GEO | 2017/04/11
SECONDARY ACCESSION(S): PRJNA306857
REPOSITORIES: GEO
Similar Datasets
Project description:The human genome folds to create thousands of loops connecting sites that are bound by the insulator protein CTCF and the ring-shaped cohesin complex. It is thought that most of these loops emerge through a process whereby cohesin extrudes chromatin, forming an initially small loop that grows larger and larger until the loop’s expansion is arrested by CTCF. Cohesin rings comprise four proteins: SMC1, SMC3, SCC1, and, in higher eukaryotes, either STAG1 or STAG2. We explore differential roles of especially STAG1, STAG2 and ESCO1 proteins in chromatin organization.
2020-02-27 | GSE138405 | GEO
Project description:Mammalian genomes contain several billion base pairs of DNA which are packaged in chromatin fibers. At selected gene loci, cohesin complexes have been proposed to arrange chromatin fibers into higher-order structures, but it is poorly understood how cohesin performs this task, how important this function is for determining the structure of chromosomes, and how this process is regulated to allow changes in gene expression. Here we show that the cohesin release factor Wapl controls chromatin structure and gene regulation at numerous loci throughout the mouse genome. Conditional deletion of the Wapl gene leads to stable accumulation of cohesin on chromatin, chromatin compaction, altered gene expression, cell cycle delay, chromosome segregation defects and embryonic lethality. In Wapl deficient chromosomes, cohesin accumulates in an axial domain, similar to how condensins form a “scaffold” in mitotic chromosomes. We propose that Wapl controls chromatin structure and gene regulation by determining the residence time with which cohesin binds to DNA. ChIP-Seq using two different antibodies (CTCF, Smc3); one (CTCF) and two (Smc3) replicates; two different genotypes (Wapl +/delta, Wapl -/delta). The control sample is a single-replicate INPUT for each genotype.
2013-08-09 | E-GEOD-41602 | biostudies-arrayexpress
Project description:DNA Double-Strand Breaks (DSBs) are highly detrimental since they can lead to mutations and chromosomes rearrangements (amplification, deletion, translocation and chromosome loss). Here, we set to assess the tridimensional genome organization around DSBs and its role in DSB repair foci formation. We performed Hi-C experiments before and after DSB induction and upon ctrl or SCC1 depletion, 4C-seq experiments before and after DSB induction and upon cohesin (SCC1) depletion or ATM inhibition. We also performed ChIP-seq of pATM(S1981), CTCF, P-SMC3(S1083), MDC1 and a calibrated ChIP-seq of SCC1 with or without damage. ChIP-chip of SMC3 (S1083) and SMC1 (S966) were used to show the recruitment of these marks on DNA repair foci. ChIP-chip of gammaH2AX was realized upon SCC1 depletion and ChIP-seq of gammaH2AX was realized upon SCC1 or WAPL to show the role of the cohesin complex in gammaH2AX foci formation. ChIP-seq of gammaH2AX was realized upon ATM or ATR inhibition to show that ATM is the major kinase that phosphorylates H2AX at clean breaks in human cells.
2021-01-29 | E-MTAB-8851 | biostudies-arrayexpress
Project description:Cohesin’s association with chromosomes is determined by loading dependent on the Scc2/4 complex and release due to Wapl. We show here that Scc2 also actively maintains cohesin on chromosomes during G1. It does so by blocking a Wapl-independent release reaction that requires opening the cohesin ring at its Smc3/Scc1 interface as well as the D loop of Smc1’s ATPase. The Wapl-independent release mechanism is switched off as cells activate Cdk1 and enter G2/M and cannot be turned back on without cohesin’s dissociation from chromosomes. The latter phenomenon enabled us to show that in the absence of release mechanisms, cohesin rings that have already captured DNA in a Scc2-dependent manner before replication no longer require Scc2 to capture sister DNAs during S phase.
2019-06-06 | GSE132221 | GEO
Project description:Sister chromatid cohesion conferred by entrapment of sister DNAs within a tripartite ring formed between cohesinâs Scc1, Smc1, and Smc3 subunits is generated during S and eventually destroyed at anaphase through cleavage of Scc1 by separase. Throughout the cell cycle, cohesinâs association with chromosomes is controlled by opposing activities: loading by the Scc2/4 complex and release by a separase independent releasing activity. Co-entrapment of sister DNAs during replication is accompanied by acetylation of Smc3 by Eco1, which blocks releasing activity and ensures that sisters remain stably connected. Because fusion of Smc3 to Scc1 prevents release and bypasses the requirement for Eco1, we suggested that release is mediated by disengagement of the Smc3/Scc1 interface. We now show that all mutations capable of bypassing Eco1, be they in cohesinâs Smc1, Smc3, Scc1,Wapl, Pds5, or Scc3 subunits, greatly reduce dissociation of N-terminal cleavage fragments of Scc1 (NScc1) from Smc3. We show that this process involves interaction between Smc ATPase heads and is inhibited by Smc3 acetylation Effect of mutations QQ and EQ in Smc3 on cohesin loading onto chromosomes
2016-02-18 | E-GEOD-76890 | biostudies-arrayexpress
Project description:Sister chromatid cohesion conferred by entrapment of sister DNAs within a tripartite ring formed between cohesin’s Scc1, Smc1, and Smc3 subunits is generated during S and eventually destroyed at anaphase through cleavage of Scc1 by separase. Throughout the cell cycle, cohesin’s association with chromosomes is controlled by opposing activities: loading by the Scc2/4 complex and release by a separase independent releasing activity. Co-entrapment of sister DNAs during replication is accompanied by acetylation of Smc3 by Eco1, which blocks releasing activity and ensures that sisters remain stably connected. Because fusion of Smc3 to Scc1 prevents release and bypasses the requirement for Eco1, we suggested that release is mediated by disengagement of the Smc3/Scc1 interface. We now show that all mutations capable of bypassing Eco1, be they in cohesin’s Smc1, Smc3, Scc1,Wapl, Pds5, or Scc3 subunits, greatly reduce dissociation of N-terminal cleavage fragments of Scc1 (NScc1) from Smc3. We show that this process involves interaction between Smc ATPase heads and is inhibited by Smc3 acetylation
2016-02-18 | GSE76890 | GEO
Project description:Cohesin is essential for genome folding and chromosome inheritance through cell divisions. In somatic cells, both of these functions are mediated by Scc1-cohesin, which in mitosis is released from chromosomes by Wapl and separase. In mammalian oocytes, cohesion is mediated by Rec8-cohesin. Scc1 is also expressed but neither required nor sufficient for cohesion, and its function in oocytes is unknown. Likewise, it is unknown whether Wapl regulates one or both cohesin complexes and chromosome segregation in mature oocytes. Using conditional mouse mutagenesis, we show that in meiosis I Wapl is required for proper chromosome segregation, predominantly releases Scc1-cohesin from chromosomes and promotes production of euploid eggs. Using single-nucleus Hi-C, we found that Scc1 is essential for chromatin loops and topologically associating domains (TADs) in oocytes. Increasing Scc1 residence time on chromosomes by Wapl depletion leads to vermicelli formation and intra-loop structures but, unlike in mitotic cells, does not increase loop size. This implies that loop size has reached a maximum in oocytes, possibly because it is limited by barriers such as cohesive cohesin. We conclude that distinct cohesin complexes generate loops and cohesion in mammalian oocytes and propose that the same principle applies to all cell types and species.
2020-03-04 | GSE132264 | GEO
Project description:Cohesin acetylation by Eco1 during DNA replication establishes sister chromatid cohesion. We show that acetylation makes cohesin resistant to Wapl activity from S-phase until mitosis. Wapl turns out to be a key regulator of cohesin dynamics on chromosomes by controling cohesin maintenance following its establishment in S-phase and its role in chromosome condensation. The Affymetrix Saccharomyces cerevisiae Chip Tiling 1.0R Arrays were used to analyze the binding pattern of Scc1 along the genome of Saccharomyces cerevisiae in late G1 and metaphase arrested cells.
2012-11-22 | E-GEOD-42457 | biostudies-arrayexpress
Project description:The spatial organization of chromosomes influences many nuclear processes including gene expression. The ring-shaped cohesin complex shapes the 3D genome by looping together convergent CTCF sites along chromosomes. We show here with high-resolution Hi-C analysis that chromatin loop size can be increased, and that cohesin’s DNA release factor WAPL restricts the degree of this extension. WAPL alsoincreased, and that cohesin’s DNA release factor WAPL restricts the degree of this extension. WAPL also prevents looping between incorrectly oriented CTCF sites. Through haploid genetics we find that WAPL deficiency bypasses the need for cohesin’s DNA loader SCC4 and we reveal that SCC4 promotes the extension of chromatin loops. We provide functional evidence in support of the model that chromatin loops are processively enlarged by the extrusion of DNA from cohesin rings. We conclude that the balanced activity of SCC4 and WAPL enables cohesin to correctly structure chromosomes to ensure proper transcriptional control.
2017-05-03 | GSE95521 | GEO
Project description:The spatial organization of chromosomes influences many nuclear processes including gene expression. The ring-shaped cohesin complex shapes the 3D genome by looping together convergent CTCF sites along chromosomes. We show here with high-resolution Hi-C analysis that chromatin loop size can be increased, and that cohesin’s DNA release factor WAPL restricts the degree of this extension. WAPL alsoincreased, and that cohesin’s DNA release factor WAPL restricts the degree of this extension. WAPL also prevents looping between incorrectly oriented CTCF sites. Through haploid genetics we find that WAPL deficiency bypasses the need for cohesin’s DNA loader SCC4 and we reveal that SCC4 promotes the extension of chromatin loops. We provide functional evidence in support of the model that chromatin loops are processively enlarged by the extrusion of DNA from cohesin rings. We conclude that the balanced activity of SCC4 and WAPL enables cohesin to correctly structure chromosomes to ensure proper transcriptional control.
2017-05-03 | GSE95520 | GEO