Genome-wide absolute quantification of chromatin looping
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE286495 | GEO | 2025/01/13
REPOSITORIES: GEO
Similar Datasets
Project description:We employed K562 CTCF MNase HiChIP to footprint CTCF & cohesin and investigate cohesin extrusion dynamics at the fragment level. We additionally re-sequenced the mouse embryonic stem cell (mESC) Region Capture Micro-C libraries from Goel et al. Nature Genetics 2023 to 150bp reads (WT, DMSO, and IAA conditions for Fbn2, Klf1, and Ppm1g loci) to verify the cohesin footprint we observed in CTCF HiChIP.
2025-01-14 | GSE285087 | GEO
Project description:In an effort to map the deeply map the structure of the genome at loci of interest, we applied Region Capture Micro-C and revealed focal patterns of contact between enhancers & promoters that we term microcompartments. We have mapped genomic structure at 0.4-1.9 Mb-sized regions at the Klf1, Ppm1g, Fbn2, Sox2, and Nanog loci across 4 conditions: wild-type and transcriptionally inhibited mouse Embryonic Stem Cells (mESCs), and cohesin-depletion & control treatments in a RAD21-AID genome-edited mESC line.
2022-07-12 | GSE207225 | GEO
Project description:We report the genome localization of R-loops in early and late-stage embryos relative to Drosophila cultured cells. We demonstrate that proper absolute R-loop levels chage during embryogenesis and that resolution of R-loops is critical for embryonic development. R-loop mapping by strand-specific DRIP-seq revealed that R-loop localization is plastic across development, both in the genes which form R-loops and where they localize relative to gene bodies. Importantly, these changes are not driven by changes in the transcriptional program. Rather, negative GC skew and absolute changes in AT skew are associated with R-loop formation in Drosophila. Furthermore, we demonstrate that while some chromatin binding proteins and histone modification such as H3K27me3 are associated with R-loops throughout development, other chromatin factors associated with R-loops in a developmental specific manner.
2022-06-21 | GSE185403 | GEO
Project description:R-loops are three stranded nucleic acid structures that accumulate on chromatin in neurological diseases and cancers and that contribute to genome instability. Using a proximity-dependent labeling system, we identified distinct classes of proteins that regulate R-loops in vivo through different mechanisms. We show that ATRX suppresses R-loops by interacting with RNAs and preventing R-loop formation. Our proteomics screen also discovered an unexpected enrichment for proteins containing zinc fingers and homeodomains at R-loops. One of the most consistently enriched proteins at R-loops was activity-dependent neuroprotective protein (ADNP), which is frequently mutated in ASD and causal in ADNP syndrome. We find that ADNP is necessary to suppress R-loops in vivo at its genomic targets and that it resolves R-loops in vitro. Furthermore, deletion of the homeodomain severely diminishes R-loop resolution activity in vitro, results in R-loop accumulation at ADNP targets and compromises neuronal differentiation. Notably, patient derived human induced pluripotent stem cells that contain an ADNP syndrome-causing mutation exhibit R-loop and CTCF accumulation at ADNP targets. Our findings point to a specific role for ADNP-mediated R-loop resolution in physiological and pathological neuronal function and, more broadly, to a previously unappreciated role for zinc finger and homeodomain proteins in R-loop regulation, with important implications for developmental disorders and cancers.
2021-06-03 | MSV000087568 | MassIVE
Project description:R-Loops are unique RNA-containing chromatin structures, which participate in various key biological processes and associate with multiple human diseases. Accurately and comprehensively profiling R-Loops in the genome is crucial to study their functions under the physiological and pathological conditions. However, the existing methodologies have produced broad discrepancies in R-Loop profiling and an independent strategy is urgently needed. Here, we constructed an artificial DNA-RNA hybrid recognition sensor protein GST-His6-2XHBD with the hybrid-binding domain of RNase H1, and found GST-His6-2XHBD could specifically interact with DNA-RNA hybrids and behaves similarly to the anti-DNA-RNA hybrid S9.6 antibody in DRIPc-seq. Furthermore, we established a convenient method, R-loop CUT&Tag, by combination of GST-His6-2XHBD with a Tn5-based cleavage under targets and tagmentation approach. R-Loop CUT&Tag generates highly specific signals for native R-Loops, and can sensitively detect the R-Loop signals at the promoter, genebody and enhancer. R-Loop CUT&Tag also provides possibilities to genome-widely map the native R-Loops with limited materials, and may benefit the resolving of the broad discrepancies between multiple R-Loop mapping methods.
2021-02-22 | GSE156400 | GEO
Project description:R-loops are dynamic, co-transcriptional nucleic acid structures that facilitate physiological processes and cause DNA damage in certain contexts. Perturbations of transcription or R-loop resolution are expected to change their genomic distribution. Next-generation sequencing approaches to map RNA:DNA hybrids, a component of R-loops, have so far not allowed quantitative comparisons between such conditions. Here we describe quantitative differential RNA:DNA immunoprecipitation (qDRIP), a method combining synthetic RNA:DNA-hybrid internal standards with high-resolution, strand-specific sequencing. We show that qDRIP avoids biases inherent to read-count normalization by accurately profiling signal in regions unaffected by transcription inhibition in human cells, and by facilitating accurate differential peak calling between conditions. Finally, we use these quantitative comparisons to make the first estimates of the absolute count of RNA:DNA hybrids per cell and their half-lives genome-wide. Overall, qDRIP allows for accurate normalization in conditions where R-loops are perturbed and for quantitative measurements that provide previously unattainable biological insights.
2020-05-29 | GSE134084 | GEO
Project description:The R-loop is a common chromatin feature presented from prokaryotic to eukaryotic genomes and has been revealed to be involved in multiple cellular processes. Here, we developed a novel R-loop profiling technique, ULI-ssDRIP-seq, to decte global R-loops from a limited number of cells. Based on this method, we profiled the R-loop landscapes during parental-to-zygotic transition and early development regulatory in zebrafish, and revealed a series of important characters of R-loops.
2024-05-29 | GSE183453 | GEO
Project description:3D chromatin structure, enhancers, and gene transcription function together to regulate cellular differentiation, establish cellular identity, and respond to external stimuli; however, the functional interplay between these regulatory elements remains incompletely understood. To infer potential causal relationships, we mapped 3D chromatin architecture, histone H3 K27 acetylation, chromatin accessibility, and gene expression across eight narrowly-spaced time points of macrophage activation. Enhancers and genes that were connected by a loop exhibited stronger correlation between histone H3K27 acetylation and expression than can be explained by distance or proximity alone, suggesting that the presence of a chromatin loop may facilitate functional regulatory connections via methods beyond simply increasing their frequency of physical proximity. Changes in enhancer acetylation preceded changes in gene expression by 30-60 minutes further supporting a causal relationship. Changes in gene expression exhibit a directional bias at differential loop anchors. The anchors of gained enhancer-promoter loops are associated with increased gene expression of genes oriented away from the center of the loop. Surprisingly, lost enhancer-promoter loops were also associated with increased gene expression, particularly within the bounds of the loop. Analysis of absolute levels of transcription revealed that lost loops were characterized by particularly high levels of internal transcription. Taken together, these results are consistent with a reciprocal relationship between looping and transcription. In this model, loops can enhance transcription by facilitating enhancer-promoter contacts, but also high levels of transcription can negatively impact loop strength by antagonizing loop extrusion mechanisms.
2022-04-30 | GSE201353 | GEO
Project description:3D chromatin structure, enhancers, and gene transcription function together to regulate cellular differentiation, establish cellular identity, and respond to external stimuli; however, the functional interplay between these regulatory elements remains incompletely understood. To infer potential causal relationships, we mapped 3D chromatin architecture, histone H3 K27 acetylation, chromatin accessibility, and gene expression across eight narrowly-spaced time points of macrophage activation. Enhancers and genes that were connected by a loop exhibited stronger correlation between histone H3K27 acetylation and expression than can be explained by distance or proximity alone, suggesting that the presence of a chromatin loop may facilitate functional regulatory connections via methods beyond simply increasing their frequency of physical proximity. Changes in enhancer acetylation preceded changes in gene expression by 30-60 minutes further supporting a causal relationship. Changes in gene expression exhibit a directional bias at differential loop anchors. The anchors of gained enhancer-promoter loops are associated with increased gene expression of genes oriented away from the center of the loop. Surprisingly, lost enhancer-promoter loops were also associated with increased gene expression, particularly within the bounds of the loop. Analysis of absolute levels of transcription revealed that lost loops were characterized by particularly high levels of internal transcription. Taken together, these results are consistent with a reciprocal relationship between looping and transcription. In this model, loops can enhance transcription by facilitating enhancer-promoter contacts, but also high levels of transcription can negatively impact loop strength by antagonizing loop extrusion mechanisms.
2022-04-30 | GSE201352 | GEO
Project description:3D chromatin structure, enhancers, and gene transcription function together to regulate cellular differentiation, establish cellular identity, and respond to external stimuli; however, the functional interplay between these regulatory elements remains incompletely understood. To infer potential causal relationships, we mapped 3D chromatin architecture, histone H3 K27 acetylation, chromatin accessibility, and gene expression across eight narrowly-spaced time points of macrophage activation. Enhancers and genes that were connected by a loop exhibited stronger correlation between histone H3K27 acetylation and expression than can be explained by distance or proximity alone, suggesting that the presence of a chromatin loop may facilitate functional regulatory connections via methods beyond simply increasing their frequency of physical proximity. Changes in enhancer acetylation preceded changes in gene expression by 30-60 minutes further supporting a causal relationship. Changes in gene expression exhibit a directional bias at differential loop anchors. The anchors of gained enhancer-promoter loops are associated with increased gene expression of genes oriented away from the center of the loop. Surprisingly, lost enhancer-promoter loops were also associated with increased gene expression, particularly within the bounds of the loop. Analysis of absolute levels of transcription revealed that lost loops were characterized by particularly high levels of internal transcription. Taken together, these results are consistent with a reciprocal relationship between looping and transcription. In this model, loops can enhance transcription by facilitating enhancer-promoter contacts, but also high levels of transcription can negatively impact loop strength by antagonizing loop extrusion mechanisms.
2022-04-30 | GSE201351 | GEO