Browse
Submit Data
Databases
API
Help

Dataset Information

33 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Fanconi anemia proteins stabilize replication forks.

ABSTRACT: Fanconi anemia (FA) is a recessive genetic disorder characterized by hypersensitivity to crosslinking agents that has been attributed to defects in DNA repair and/or replication. FANCD2 and the FA core complex bind to chromatin during DNA replication; however, the role of FA proteins during replication is unknown. Using Xenopus cell-free extracts, we show that FANCL depletion results in defective DNA replication restart following treatment with camptothecin, a drug that results in DSBs during DNA replication. This defect is more pronounced following treatment with mitomycin C, presumably because of an additional role of the FA pathway in DNA crosslink repair. Moreover, we show that chromatin binding of FA core complex proteins during DNA replication follows origin assembly and origin firing and is dependent on the binding of RPA to ssDNA while FANCD2 additionally requires ATR, consistent with FA proteins acting at replication forks. Together, our data suggest that FA proteins play a role in replication restart at collapsed replication forks.

SUBMITTER: Wang LC

PROVIDER: S-EPMC2596863 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Fanconi anemia proteins stabilize replication forks.

Wang Lily Chien LC Stone Stacie S Hoatlin Maureen Elizabeth ME Gautier Jean J

DNA repair 20080925 12

Fanconi anemia (FA) is a recessive genetic disorder characterized by hypersensitivity to crosslinking agents that has been attributed to defects in DNA repair and/or replication. FANCD2 and the FA core complex bind to chromatin during DNA replication; however, the role of FA proteins during replication is unknown. Using Xenopus cell-free extracts, we show that FANCL depletion results in defective DNA replication restart following treatment with camptothecin, a drug that results in DSBs during DN ...[more]

PMID: 18786657

Similar Datasets

Fanconi anemia proteins are required to prevent accumulation of replication-associated DNA double-strand breaks.

Project description:Fanconi anemia (FA) is a multigene cancer susceptibility disorder characterized by cellular hypersensitivity to DNA interstrand cross-linking agents such as mitomycin C (MMC). FA proteins are suspected to function at the interface between cell cycle checkpoints, DNA repair, and DNA replication. Using replicating extracts from Xenopus eggs, we developed cell-free assays for FA proteins (xFA). Recruitment of the xFA core complex and xFANCD2 to chromatin is strictly dependent on replication initiation, even in the presence of MMC indicating specific recruitment to DNA lesions encountered by the replication machinery. The increase in xFA chromatin binding following treatment with MMC is part of a caffeine-sensitive S-phase checkpoint that is controlled by xATR. Recruitment of xFANCD2, but not xFANCA, is dependent on the xATR-xATR-interacting protein (xATRIP) complex. Immunodepletion of either xFANCA or xFANCD2 from egg extracts results in accumulation of chromosomal DNA breaks during replicative synthesis. Our results suggest coordinated chromatin recruitment of xFA proteins in response to replication-associated DNA lesions and indicate that xFA proteins function to prevent the accumulation of DNA breaks that arise during unperturbed replication.

| S-EPMC1346898 | biostudies-literature

Human Timeless and Tipin stabilize replication forks and facilitate sister-chromatid cohesion.

Project description:The Timeless-Tipin protein complex has been reported to be important for replication checkpoint and normal DNA replication processes. However, the precise mechanisms by which Timeless-Tipin preserves genomic integrity are largely unclear. Here, we describe the roles of Timeless-Tipin in replication fork stabilization and sister chromatid cohesion. We show in human cells that Timeless is recruited to replication origin regions and dissociate from them as replication proceeds. Cdc45, which is known to be required for replication fork progression, shows similar patterns of origin association to those of Timeless. Depletion of Timeless-Tipin causes chromosome fragmentation and defects in damage repair in response to fork collapse, suggesting that it is required for replication fork maintenance under stress. We also demonstrate that depletion of Timeless-Tipin impairs sister chromatid cohesion and causes a defect in mitotic progression. Consistently, Timeless-Tipin co-purifies with cohesin subunits and is required for their stable association with chromatin during S phase. Timeless associates with the cohesion-promoting DNA helicase ChlR1, which, when overexpressed, partially alleviates the cohesion defect of cells depleted of Timeless-Tipin. These results suggest that Timeless-Tipin functions as a replication fork stabilizer that couples DNA replication with sister chromatid cohesion established at replication forks.

| S-EPMC2823575 | biostudies-literature

Fanconi Anemia Proteins Function in Mitophagy and Immunity.

Project description:Fanconi anemia (FA) pathway genes are important tumor suppressors whose best-characterized function is repair of damaged nuclear DNA. Here, we describe an essential role for FA genes in two forms of selective autophagy. Genetic deletion of Fancc blocks the autophagic clearance of viruses (virophagy) and increases susceptibility to lethal viral encephalitis. Fanconi anemia complementation group C (FANCC) protein interacts with Parkin, is required in vitro and in vivo for clearance of damaged mitochondria, and decreases mitochondrial reactive oxygen species (ROS) production and inflammasome activation. The mitophagy function of FANCC is genetically distinct from its role in genomic DNA damage repair. Moreover, additional genes in the FA pathway, including FANCA, FANCF, FANCL, FANCD2, BRCA1, and BRCA2, are required for mitophagy. Thus, members of the FA pathway represent a previously undescribed class of selective autophagy genes that function in immunity and organellar homeostasis. These findings have implications for understanding the pathogenesis of FA and cancers associated with mutations in FA genes.

| S-EPMC4881391 | biostudies-literature

Promyelocytic Leukemia Proteins Regulate Fanconi Anemia Gene Expression.

Project description:Promyelocytic leukemia (PML) protein is the core component of subnuclear structures called PML nuclear bodies that are known to play important roles in cell survival, DNA damage responses, and DNA repair. Fanconi anemia (FA) proteins are required for repairing interstrand DNA crosslinks (ICLs). Here we report a novel role of PML proteins, regulating the ICL repair pathway. We found that depletion of the PML protein led to the significant reduction of damage-induced FANCD2 mono-ubiquitination and FANCD2 foci formation. Consistently, the cells treated with siRNA against PML showed enhanced sensitivity to a crosslinking agent, mitomycin C. Further studies showed that depletion of PML reduced the protein expression of FANCA, FANCG, and FANCD2 via reduced transcriptional activity. Interestingly, we observed that damage-induced CHK1 phosphorylation was severely impaired in cells with depleted PML, and we demonstrated that CHK1 regulates FANCA, FANCG, and FANCD2 transcription. Finally, we showed that inhibition of CHK1 phosphorylation further sensitized cancer cells to mitomycin C. Taken together, these findings suggest that the PML is critical for damage-induced CHK1 phosphorylation, which is important for FA gene expression and for repairing ICLs.

| S-EPMC8346011 | biostudies-literature

Recruitment of fanconi anemia and breast cancer proteins to DNA damage sites is differentially governed by replication.

Project description:Fanconi anemia (FA) is characterized by cellular hypersensitivity to DNA crosslinking agents, but how the Fanconi pathway protects cells from DNA crosslinks and whether FA proteins act directly on crosslinks remain unclear. We developed a chromatin-IP-based strategy termed eChIP and detected association of multiple FA proteins with DNA crosslinks in vivo. Interdependence analyses revealed that crosslink-specific enrichment of various FA proteins is controlled by distinct mechanisms. BRCA-related FA proteins (BRCA2, FANCJ/BACH1, and FANCN/PALB2), but not FA core and I/D2 complexes, require replication for their crosslink association. FANCD2, but not FANCJ and FANCN, requires the FA core complex for its recruitment. FA core complex requires nucleotide excision repair proteins XPA and XPC for its association. Consistent with the distinct recruitment mechanism, recombination-independent crosslink repair was inversely affected in cells deficient of FANC-core versus BRCA-related FA proteins. Thus, FA proteins participate in distinct DNA damage response mechanisms governed by DNA replication status.

| S-EPMC2758766 | biostudies-literature

Mutated Fanconi anemia pathway in non-Fanconi anemia cancers.

Project description:An extremely high cancer incidence and the hypersensitivity to DNA crosslinking agents associated with Fanconi Anemia (FA) have marked it to be a unique genetic model system to study human cancer etiology and treatment, which has emerged an intense area of investigation in cancer research. However, there is limited information about the relationship between the mutated FA pathway and the cancer development or/and treatment in patients without FA. Here we analyzed the mutation rates of the seventeen FA genes in 68 DNA sequence datasets. We found that the FA pathway is frequently mutated across a variety of human cancers, with a rate mostly in the range of 15 to 35 % in human lung, brain, bladder, ovarian, breast cancers, or others. Furthermore, we found a statistically significant correlation (p < 0.05) between the mutated FA pathway and the development of human bladder cancer that we only further analyzed. Together, our study demonstrates a previously unknown fact that the mutated FA pathway frequently occurs during the development of non-FA human cancers, holding profound implications directly in advancing our understanding of human tumorigenesis as well as tumor sensitivity/resistance to crosslinking drug-relevant chemotherapy.

| S-EPMC4653013 | biostudies-literature

The Fanconi anemia pathway in replication stress and DNA crosslink repair.

Project description:Interstand crosslinks (ICLs) are DNA lesions where the bases of opposing DNA strands are covalently linked, inhibiting critical cellular processes such as transcription and replication. Chemical agents that generate ICLs cause chromosomal abnormalities including breaks, deletions and rearrangements, making them highly genotoxic compounds. This toxicity has proven useful for chemotherapeutic treatment against a wide variety of cancer types. The majority of our understanding of ICL repair in humans has been uncovered through analysis of the rare genetic disorder Fanconi anemia, in which patients are extremely sensitive to crosslinking agents. Here, we discuss recent insights into ICL repair gained using new repair assays and highlight the role of the Fanconi anemia repair pathway during replication stress.

| S-EPMC3890373 | biostudies-literature

Tousled-like kinases stabilize replication forks and show synthetic lethality with checkpoint and PARP inhibitors.

Project description:DNA sequence and epigenetic information embedded in chromatin must be faithfully duplicated and transmitted to daughter cells during cell division. However, how chromatin assembly and DNA replication are integrated remains unclear. We examined the contribution of the Tousled-like kinases 1 and 2 (TLK1/TLK2) to chromatin assembly and maintenance of replication fork integrity. We show that TLK activity is required for DNA replication and replication-coupled nucleosome assembly and that lack of TLK activity leads to replication fork stalling and the accumulation of single-stranded DNA, a phenotype distinct from ASF1 depletion. Consistent with these results, sustained TLK depletion gives rise to replication-dependent DNA damage and p53-dependent cell cycle arrest in G1. We find that deficient replication-coupled de novo nucleosome assembly renders replication forks unstable and highly dependent on the ATR and CHK1 checkpoint kinases, as well as poly(adenosine 5'-diphosphate-ribose) polymerase (PARP) activity, to avoid collapse. Human cancer data revealed frequent up-regulation of TLK genes and an association with poor patient outcome in multiple types of cancer, and depletion of TLK activity leads to increased replication stress and DNA damage in a panel of cancer cells. Our results reveal a critical role for TLKs in chromatin replication and suppression of replication stress and identify a synergistic lethal relationship with checkpoint signaling and PARP that could be exploited in treatment of a broad range of cancers.

| S-EPMC6082654 | biostudies-literature

The Fanconi anemia pathway promotes replication-dependent DNA interstrand cross-link repair.

Project description:Fanconi anemia is a human cancer predisposition syndrome caused by mutations in 13 Fanc genes. The disorder is characterized by genomic instability and cellular hypersensitivity to chemicals that generate DNA interstrand cross-links (ICLs). A central event in the activation of the Fanconi anemia pathway is the mono-ubiquitylation of the FANCI-FANCD2 complex, but how this complex confers ICL resistance remains enigmatic. Using a cell-free system, we showed that FANCI-FANCD2 is required for replication-coupled ICL repair in S phase. Removal of FANCD2 from extracts inhibits both nucleolytic incisions near the ICL and translesion DNA synthesis past the lesion. Reversal of these defects requires ubiquitylated FANCI-FANCD2. Our results show that multiple steps of the essential S-phase ICL repair mechanism fail when the Fanconi anemia pathway is compromised.

| S-EPMC2909596 | biostudies-literature

Replication Protein A (RPA) deficiency activates the Fanconi anemia DNA repair pathway.

Project description:The Fanconi anemia (FA) pathway regulates DNA inter-strand crosslink (ICL) repair. Despite our greater understanding of the role of FA in ICL repair, its function in the preventing spontaneous genome instability is not well understood. Here, we show that depletion of replication protein A (RPA) activates the FA pathway. RPA1 deficiency increases chromatin recruitment of FA core complex, leading to FANCD2 monoubiquitination (FANCD2-Ub) and foci formation in the absence of DNA damaging agents. Importantly, ATR depletion, but not ATM, abolished RPA1 depletion-induced FANCD2-Ub, suggesting that ATR activation mediated FANCD2-Ub. Interestingly, we found that depletion of hSSB1/2-INTS3, a single-stranded DNA-binding protein complex, induces FANCD2-Ub, like RPA1 depletion. More interestingly, depletion of either RPA1 or INTS3 caused increased accumulation of DNA damage in FA pathway deficient cell lines. Taken together, these results indicate that RPA deficiency induces activation of the FA pathway in an ATR-dependent manner, which may play a role in the genome maintenance.

| S-EPMC5004677 | 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