Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Dynamics of de novo heterochromatin assembly and disassembly at replication forks ensures fork stability

ABSTRACT: Chromatin is dynamically reorganized when DNA replication forks are challenged. However, the process of epigenetic reorganization and its implication for fork stability is poorly understood. Here, we discover a checkpoint regulated cascade of chromatin signaling that activates the histone methyltransferase EHMT2/G9a to catalyze heterochromatin assembly at stressed replication forks. Using biochemical and single molecule chromatin fiber approaches, we show that G9a together with SUV39h1 induces chromatin condensation by accumulating the silent mark, H3K9me1/2/3, in the vicinity of stressed replication forks. This closed conformation is also favored by the G9a-dependent exclusion of the H3K9-demethylase JMJD1A/KDM3A, which facilitates heterochromatin disassembly upon fork restart. Untimely heterochromatin disassembly from stressed forks by KDM3A enables PRIMPOL access, triggering ssDNA gaps formation and sensitizing cells towards chemotherapeutic drugs. These findings may help explaining chemotherapy resistance and poor prognosis observed in cancer patients displaying elevated level of G9a/H3K9me3.modifications (PTMs) in a single mass spectrum. Combined with immunoprecipitation, Nuc-MS quantified nucleosome co-occupancy of histone H3.3 with variant H2A.Z (sixfold over bulk) and the co-occurrence of oncogenic H3.3K27M with euchromatic marks (for example, a >15-fold enrichment of dimethylated H3K79me2). Nuc-MS is highly concordant with chromatin immunoprecipitation-sequencing (ChIP-seq) and offers a new readout of nucleosome-level biology.

ORGANISM(S): Homo sapiens

PROVIDER: GSE220073 | GEO | 2024/11/30

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Dynamics of de novo heterochromatin assembly and disassembly at replication forks ensures fork stability

Project description:Chromatin is dynamically reorganized when DNA replication forks are challenged. However, the process of epigenetic reorganization and its implication for fork stability is poorly understood. Here, we discover a checkpoint regulated cascade of chromatin signaling that activates 5 the histone methyltransferase EHMT2/G9a to catalyze heterochromatin assembly at stressed replication forks. Using biochemical and single molecule chromatin fiber approaches, we show that G9a together with SUV39h1 induces chromatin compaction by accumulating the repressive modifications, H3K9me1/me2/me3, in the vicinity of stressed replication forks. This closed conformation is also favored by the G9a-dependent exclusion of the H3K9-demethylase 10 JMJD1A/KDM3A, which facilitates heterochromatin disassembly upon fork restart. Untimely heterochromatin disassembly from stressed forks by KDM3A enables PRIMPOL access, triggering ssDNA gap formation and sensitizing cells towards chemotherapeutic drugs. These findings may help explaining chemotherapy resistance and poor prognosis observed in cancer patients displaying elevated level of G9a/H3K9me3.

2023-05-12 | PXD041742 | Pride

Project description:Dynamics of de novo heterochromatin assembly and disassembly at replication forks ensures fork stability

| PRJNA897702 | ENA

RNAi promotes heterochromatic silencing through replication-coupled release of RNA pol II (RNA seq)

Project description:Heterochromatin comprises tightly compacted repetitive regions of eukaryotic chromosomes. The inheritance of heterochromatin through mitosis requires RNA interference (RNAi), which guides histone modification during the DNA replication phase of the cell cycle. Here, we show that the alternating arrangement of origins of replication and non-coding RNA in pericentromeric heterochromatin results in competition between transcription and replication. Co-transcriptional RNAi releases RNA polymerase II (PolII), allowing completion of DNA replication by the leading strand DNA polymerase, and associated histone modifying enzymes which spread heterochromatin with the replication fork. In the absence of RNAi, stalled forks are repaired by homologous recombination without histone modification. small RNA cloning from wild type and dcr1-deleted strains

2011-07-21 | E-GEOD-30827 | biostudies-arrayexpress

RNAi promotes heterochromatic silencing through replication-coupled release of RNA pol II (ChIP-seq)

Project description:Heterochromatin comprises tightly compacted repetitive regions of eukaryotic chromosomes. The inheritance of heterochromatin through mitosis requires RNA interference (RNAi), which guides histone modification 1 during the DNA replication phase of the cell cycle2. Here, we show that the alternating arrangement of origins of replication and non-coding RNA in pericentromeric heterochromatin results in competition between transcription and replication. Co-transcriptional RNAi releases RNA polymerase II (PolII), allowing completion of DNA replication by the leading strand DNA polymerase, and associated histone modifying enzymes3 which spread heterochromatin with the replication fork. In the absence of RNAi, stalled forks are repaired by homologous recombination without histone modification. RNA PolII ChIP from wild type and dcr1-deleted samples in exponentially growing and HU-arrested cultures.

2011-07-29 | E-GEOD-31016 | biostudies-arrayexpress

SLFN11 blocks stressed replication forks independently of ATR

Project description:SLFN11 sensitizes cancer cells to a broad range of DNA-targeted therapies. Here we show that, in response to replication stress induced by camptothecin, SLFN11 tightly binds chromatin at stressed replication foci via RPA1 together with the replication helicase subunit MCM3. Unlike ATR, SLFN11 neither interferes with the loading of CDC45 and PCNA nor inhibits the initiation of DNA replication but selectively blocks fork progression while inducing chromatin opening across replication initiation sites. The ATPase domain of SLFN11 is required for chromatin opening, replication block and cell death but not for the tight binding of SLFN11 to chromatin. Replication stress by the CHK1 inhibitor Prexasertib also recruits SLFN11 to nascent replicating DNA together with CDC45 and PCNA. We conclude that SLFN11 is recruited to stressed replication forks carrying extended RPA filaments where it blocks replication by changing chromatin structure across replication sites.

2018-01-18 | GSE101516 | GEO

SLFN11 blocks stressed replication forks independently of ATR (NS-Seq)

2018-01-18 | GSE101515 | GEO

SLFN11 blocks stressed replication forks independently of ATR

2018-01-18 | GSE101512 | GEO

A chromatin-associated long non-coding RNA is required for effective replication stress signaling [RNAseq_cell_cycle]

Project description:Despite the well-characterized protein network involved in replication stress response, several regulatory RNAs have been shown to be involved in this process; however, it has remained elusive the presence of such RNAs on the replication fork, and how they locally act in this critical process. Here, we identified lncREST, a previously uncharacterized lncRNA among a set of chromatin-associated transcripts induced by hydroxyurea. We show that lncREST localizes on stressed replication forks. Specifically, during replication stress, lncREST interacts with NCL in the nucleus, to help engage its interaction with RPA. Consequently, lncREST loss is associated to reduction of NCL-RPA interaction and decreased RPA on chromatin, leading to a defective replication stress signaling. lncREST depleted cells suffer sustained replication fork progression and accumulate un-signaled DNA damage. These findings uncover a structural function of a lncRNA acting as anchoring point for replication proteins foci on sites of DNA replication.

2023-12-18 | GSE229869 | GEO

A chromatin-associated long non-coding RNA is required for effective replication stress signaling [RNAseq_HUtreatment]

2023-12-18 | GSE229868 | GEO

PARP1 proximity proteomics reveals interaction partners at stressed replication forks

Project description:PARP1 mediates poly-ADP-ribosylation of proteins on chromatin in response to different types of DNA lesions. PARP inhibitors are used for the treatment of BRCA1/2-deficient breast, ovarian, and prostate cancer. Loss of DNA replication fork protection is proposed as one mechanism that contributes to the vulnerability of BRCA1/2-deficient cells to PARP inhibitors. However, the mechanisms that regulate PARP1 activity at stressed replication forks remain poorly understood. Here, we performed proximity proteomics of PARP1 and isolation of proteins on stressed replication forks to map putative PARP1 regulators. We identified TPX2 as a direct PARP1-binding protein that regulates the auto-ADP-ribosylation activity of PARP1. TPX2 interacts with DNA damage response proteins and promotes homology-directed repair of DNA double-strand breaks. Moreover, TPX2 mRNA levels are increased in BRCA1/2-mutated breast and prostate cancers, and high TPX2 expression levels correlate with the sensitivity of cancer cells to PARP-trapping inhibitors. We propose that TPX2 confers a mitosis-independent function in the cellular response to replication stress by interacting with PARP1.

2022-10-11 | PXD037154 | Pride

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data