Browse
Submit Data
Databases
API
Help

Dataset Information

33 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

MUS81-EME2 promotes replication fork restart.

ABSTRACT: Replication forks frequently stall at regions of the genome that are difficult to replicate or contain lesions that cause replication blockage. An important mechanism for the restart of a stalled fork involves endonucleolytic cleavage that can lead to fork restoration and replication progression. Here, we show that the structure-selective endonuclease MUS81-EME2 is responsible for fork cleavage and restart in human cells. The MUS81-EME2 protein, whose actions are restricted to S phase, is also responsible for telomere maintenance in telomerase-negative ALT (Alternative Lengthening of Telomeres) cells. In contrast, the G2/M functions of MUS81, such as the cleavage of recombination intermediates and fragile site expression, are promoted by MUS81-EME1. These results define distinct and temporal roles for MUS81-EME1 and MUS81-EME2 in the maintenance of genome stability.

SUBMITTER: Pepe A

PROVIDER: S-EPMC5092538 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

MUS81-EME2 promotes replication fork restart.

Pepe Alessandra A West Stephen C SC

Cell reports 20140509 4

Replication forks frequently stall at regions of the genome that are difficult to replicate or contain lesions that cause replication blockage. An important mechanism for the restart of a stalled fork involves endonucleolytic cleavage that can lead to fork restoration and replication progression. Here, we show that the structure-selective endonuclease MUS81-EME2 is responsible for fork cleavage and restart in human cells. The MUS81-EME2 protein, whose actions are restricted to S phase, is also r ...[more]

PMID: 24813886

Similar Datasets

Human CST promotes telomere duplex replication and general replication restart after fork stalling.

Project description:Mammalian CST (CTC1-STN1-TEN1) associates with telomeres and depletion of CTC1 or STN1 causes telomere defects. However, the function of mammalian CST remains poorly understood. We show here that depletion of CST subunits leads to both telomeric and non-telomeric phenotypes associated with DNA replication defects. Stable knockdown of CTC1 or STN1 increases the incidence of anaphase bridges and multi-telomeric signals, indicating genomic and telomeric instability. STN1 knockdown also delays replication through the telomere indicating a role in replication fork passage through this natural barrier. Furthermore, we find that STN1 plays a novel role in genome-wide replication restart after hydroxyurea (HU)-induced replication fork stalling. STN1 depletion leads to reduced EdU incorporation after HU release. However, most forks rapidly resume replication, indicating replisome integrity is largely intact and STN1 depletion has little effect on fork restart. Instead, STN1 depletion leads to a decrease in new origin firing. Our findings suggest that CST rescues stalled replication forks during conditions of replication stress, such as those found at natural replication barriers, likely by facilitating dormant origin firing.

| S-EPMC3433780 | biostudies-literature

Cohesin association to replication sites depends on rad50 and promotes fork restart.

Project description:The cohesin complex holds together newly replicated chromatids and is involved in diverse pathways that preserve genome integrity. We show that in budding yeast, cohesin is transiently recruited to active replication origins, and it spreads along DNA as forks progress. When DNA synthesis is impeded, cohesin accumulates at replication sites and is critical for the recovery of stalled forks. Cohesin enrichment at replication forks does not depend on ?H2A(X) formation, which differs from its loading requirements at DNA double-strand breaks (DSBs). However, cohesin localization is largely reduced in rad50? mutants and in cells lacking both Mec1 and Tel1 checkpoint kinases. Interestingly, cohesin loading at replication sites depends on the structural features of Rad50 that are important for bridging sister chromatids, including the CXXC hook domain and the length of the coiled-coil extensions. Together, these data reveal a function for cohesin in the maintenance of genome integrity during S phase.

| S-EPMC3904740 | biostudies-literature

RIF1 promotes replication fork protection and efficient restart to maintain genome stability.

Project description:Homologous recombination (HR) and Fanconi Anemia (FA) pathway proteins in addition to their DNA repair functions, limit nuclease-mediated processing of stalled replication forks. However, the mechanism by which replication fork degradation results in genome instability is poorly understood. Here, we identify RIF1, a non-homologous end joining (NHEJ) factor, to be enriched at stalled replication forks. Rif1 knockout cells are proficient for recombination, but displayed degradation of reversed forks, which depends on DNA2 nuclease activity. Notably, RIF1-mediated protection of replication forks is independent of its function in NHEJ, but depends on its interaction with Protein Phosphatase 1. RIF1 deficiency delays fork restart and results in exposure of under-replicated DNA, which is the precursor of subsequent genomic instability. Our data implicate RIF1 to be an essential factor for replication fork protection, and uncover the mechanisms by which unprotected DNA replication forks can lead to genome instability in recombination-proficient conditions.

| S-EPMC6650494 | biostudies-literature

Cells defective for replication restart undergo replication fork reversal.

Project description:We have studied the fate of blocked replication forks with the use of the Escherichia coli priA mutant, in which spontaneously arrested replication forks persist owing to the lack of the major replication restart pathway. Such blocked forks undergo a specific reaction named replication fork reversal, in which newly synthesized strands anneal to form a DNA double-strand end adjacent to a four-way junction. Indeed, (i) priA recB mutant chromosomes are linearized by a reaction that requires the presence of the Holliday junction resolvase RuvABC, and (ii) RuvABC-dependent linearization is prevented by the presence of RecBC. Replication fork reversal in a priA mutant occurs independently of the recombination proteins RecA and RecR. recBC inactivation does not affect priA mutant viability but prevents priA chronic SOS induction. We propose that, in the absence of PriA, RecBC action at reversed forks does not allow replication restart, which leads to the accumulation of SOS-inducing RecA filaments. Our results suggest that types of replication blockage that cause replication fork reversal occur spontaneously.

| S-EPMC1299077 | biostudies-literature

Cohesin association to replication sites depends on Rad50 and promotes fork restart

Project description:The cohesin complex holds together newly-replicated chromatids and is involved in diverse pathways that preserve genome integrity. We show that in budding yeast, cohesin is transiently recruited to active replication origins and it spreads along DNA as forks progress. When DNA synthesis is impeded, cohesin accumulates at replication sites and is critical for the recovery of stalled forks. Cohesin enrichment at replication forks does not depend on H2A(X) formation, which differs from its loading requirements at DNA double-strand breaks (DSBs). However, cohesin localization is largely reduced in rad50delta mutants and cells lacking both Mec1 and Tel1 checkpoint kinases. Interestingly, cohesin loading at replication sites depends on the structural features of Rad50 that are important for bridging sister chromatids, including the CXXC hook domain and the length of the coiled-coil extensions. Together, these data reveal a novel function for cohesin in the maintenance of genome integrity during S phase. Scc1 ChIP, Rad50 ChIP and BrdU IP in wild type and mutants at different stages of the cell cycle.

2012-10-01 | E-GEOD-39078 | biostudies-arrayexpress

WRNIP1 protects stalled forks from degradation and promotes fork restart after replication stress.

Project description:Accurate handling of stalled replication forks is crucial for the maintenance of genome stability. RAD51 defends stalled replication forks from nucleolytic attack, which otherwise can threaten genome stability. However, the identity of other factors that can collaborate with RAD51 in this task is poorly elucidated. Here, we establish that human Werner helicase interacting protein 1 (WRNIP1) is localized to stalled replication forks and cooperates with RAD51 to safeguard fork integrity. We show that WRNIP1 is directly involved in preventing uncontrolled MRE11-mediated degradation of stalled replication forks by promoting RAD51 stabilization on ssDNA We further demonstrate that replication fork protection does not require the ATPase activity of WRNIP1 that is however essential to achieve the recovery of perturbed replication forks. Loss of WRNIP1 or its catalytic activity causes extensive DNA damage and chromosomal aberrations. Intriguingly, downregulation of the anti-recombinase FBH1 can compensate for loss of WRNIP1 activity, since it attenuates replication fork degradation and chromosomal aberrations in WRNIP1-deficient cells. Therefore, these findings unveil a unique role for WRNIP1 as a replication fork-protective factor in maintaining genome stability.

| S-EPMC4931187 | biostudies-literature

XRCC1 promotes replication restart, nascent fork degradation and mutagenic DNA repair in BRCA2-deficient cells.

Project description:Homologous recombination/end joining (HR/HEJ)-deficient cancers with BRCA mutations utilize alternative DNA double-strand break repair pathways, particularly alternative non-homologous end joining or microhomology-mediated end joining (alt-EJ/MMEJ) during S and G2 cell cycle phases. Depletion of alt-EJ factors, including XRCC1, PARP1 and POLQ, is synthetically lethal with BRCA2 deficiency; yet, XRCC1 roles in HR-deficient cancers and replication stress are enigmatic. Here, we show that after replication stress, XRCC1 forms an active repair complex with POLQ and MRE11 that supports alt-EJ activity in vitro. BRCA2 limits XRCC1 recruitment and repair complex formation to suppress alt-EJ at stalled forks. Without BRCA2 fork protection, XRCC1 enables cells to complete DNA replication at the expense of increased genome instability by promoting MRE11-dependent fork resection and restart. High XRCC1 and MRE11 gene expression negatively impacts Kaplan-Meier survival curves and hazard ratios for HR-deficient breast cancer patients in The Cancer Genome Atlas. The additive effects of depleting both BRCA2 and XRCC1 indicate distinct pathways for replication restart. Our collective data show that XRCC1-mediated processing contributes to replication fork degradation, replication restart and chromosome aberrations in BRCA2-deficient cells, uncovering new roles of XRCC1 and microhomology-mediated repair mechanisms in HR-deficient cancers, with implications for chemotherapeutic strategies targeting POLQ and PARP activities.

| S-EPMC7397735 | biostudies-literature

SETD2-mediated H3K14 trimethylation promotes ATR activation and stalled replication fork restart in response to DNA replication stress.

Project description:Ataxia telangiectasia and Rad3 related (ATR) activation after replication stress involves a cascade of reactions, including replication protein A (RPA) complex loading onto single-stranded DNA and ATR activator loading onto chromatin. The contribution of histone modifications to ATR activation, however, is unclear. Here, we report that H3K14 trimethylation responds to replication stress by enhancing ATR activation. First, we confirmed that H3K14 monomethylation, dimethylation, and trimethylation all exist in mammalian cells, and that both SUV39H1 and SETD2 methyltransferases can catalyze H3K14 trimethylation in vivo and in vitro. Interestingly, SETD2-mediated H3K14 trimethylation markedly increases in response to replication stress induced with hydroxyurea, a replication stress inducer. Under these conditions, SETD2-mediated H3K14me3 recruited the RPA complex to chromatin via a direct interaction with RPA70. The increase in H3K14me3 levels was abolished, and RPA loading was attenuated when SETD2 was depleted or H3K14 was mutated. Rather, the cells were sensitive to replication stress such that the replication forks failed to restart, and cell-cycle progression was delayed. These findings help us understand how H3K14 trimethylation links replication stress with ATR activation.

| S-EPMC8201831 | biostudies-literature

Cohesin association to replication sites depends on Rad50 and promotes fork restart

2012-10-01 | GSE39078 | GEO

Direct observation of stalled fork restart via fork regression in the T4 replication system.

Project description:The restart of a stalled replication fork is a major challenge for DNA replication. Depending on the nature of the damage, different repair processes might be triggered; one is template switching, which is a bypass of a leading-strand lesion via fork regression. Using magnetic tweezers to study the T4 bacteriophage enzymes, we have reproduced in vitro the complete process of template switching. We show that the UvsW DNA helicase in cooperation with the T4 holoenzyme can overcome leading-strand lesion damage by a pseudostochastic process, periodically forming and migrating a four-way Holliday junction. The initiation of the repair process requires partial replisome disassembly via the departure of the replicative helicase. The results support the role of fork regression pathways in DNA repair.

| S-EPMC3858903 | biostudies-literature

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