Saccharomyces cerevisiae
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA449230 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR7000910.fastq.gz | Fastqsanger.gz | |||
| SRR7000920.fastq.gz | Fastqsanger.gz | |||
| SRR7000930.fastq.gz | Fastqsanger.gz | |||
| SRR7000940.fastq.gz | Fastqsanger.gz | |||
| SRR7000950.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 82 |
Similar Datasets
Project description:Lesions on DNA can uncouple DNA synthesis from helicase unwinding, generating stretches of unreplicated single stranded DNA (ssDNA) behind the replication fork. These ssDNA gaps need to be filled in to complete DNA duplication and thereby avoid the generation of DNA double-stranded breaks (DSBs), a major source of genomic instability. Gap filling repair involves either translesion DNA synthesis (TLS) or template switching (TS) to bypass the lesion. At the heart of these processes, ubiquitylated PCNA recruits many proteins that dictate pathway choice, but the enzymes regulating PCNA ubiquitylation in vertebrates remain poorly defined. Here we report that the E3 ubiquitin ligase RFWD3 promotes non-specific ubiquitylation of proteins on ssDNA, to enhance protein accumulation and stimulate gap filling repair. The absence of RFWD3 leads to a profound defect in recruitment of key repair and signaling factors to damaged chromatin, including ubiquitin and proteins known to ubiquitylate and interact with ubiquitylated PCNA. As a result, PCNA ubiquitylation is severely inhibited without RFWD3, and TLS across different DNA lesions drastically impaired. We propose that RFWD3 is an essential coordinator of the response to ssDNA gaps, where it triggers wide spread ubiquitylation to drive recruitment of effectors of PCNA ubiquitylation and DNA damage bypass.
2020-12-15 | PXD018217 | Pride
Project description:Lesions on DNA can uncouple DNA synthesis from helicase unwinding, generating stretches of unreplicated single stranded DNA (ssDNA) behind the replication fork. These ssDNA gaps need to be filled in to complete DNA duplication and thereby avoid the generation of DNA double-stranded breaks (DSBs), a major source of genomic instability. Gap filling repair involves either translesion DNA synthesis (TLS) or template switching (TS) to bypass the lesion. At the heart of these processes, ubiquitylated PCNA recruits many proteins that dictate pathway choice, but the enzymes regulating PCNA ubiquitylation in vertebrates remain poorly defined. Here we report that the E3 ubiquitin ligase RFWD3 promotes non-specific ubiquitylation of proteins on ssDNA, to enhance protein accumulation and stimulate gap filling repair. The absence of RFWD3 leads to a profound defect in recruitment of key repair and signaling factors to damaged chromatin, including ubiquitin and proteins known to ubiquitylate and interact with ubiquitylated PCNA. As a result, PCNA ubiquitylation is severely inhibited without RFWD3, and TLS across different DNA lesions drastically impaired. We propose that RFWD3 is an essential coordinator of the response to ssDNA gaps, where it triggers non-specific ubiquitylation to drive recruitment of effectors of PCNA ubiquitylation and DNA damage bypass.
2020-12-15 | PXD021445 | Pride
Project description:Here we report our observations that have led us to propose that the transcription elongation factor NusA promotes a novel class of transcription-coupled repair (TCR) in addition to its previously proposed role in recruiting translesion synthesis (TLS) DNA polymerases to gaps encountered during transcription. Earlier we have reported that NusA physically and genetically interacts with the TLS DNA polymerase DinB (DNA pol IV). We find that Escherichia coli nusA11(ts) mutant strains, at the permissive temperature, are highly sensitive to nitrofurazone (NFZ) and 4-nitroquinolone-1-oxide but not to ultraviolet radiation. Gene expression profiling suggests this sensitivity is unlikely to be due to an indirect effect on gene expression affecting a known DNA repair or damage tolerance pathway. We demonstrate that an N2-furfuryl-dG (N2-f-dG) lesion, a structural analog of the principal lesion generated by NFZ, blocks transcription by E. coli RNA polymerase (RNAP) when present in the transcribed strand, but not when present in the non-transcribed strand. Our genetic analysis suggests that NusA participates in a nucleotide excision repair (NER)-dependent process to promote NFZ resistance. We provide evidence that transcription plays a role in the repair of NFZ-induced lesions through the isolation of RNAP mutants that display altered ability to survive NFZ exposure. We propose that NusA participates in a novel class of TCR involved in the identification and removal of a class of lesion, such as the N2-f-dG lesion, which are accurately and efficiently bypassed by DinB in addition to recruiting DinB for TLS at gaps encountered by RNAP. Wild-type and nusA11 samples were analyzed, with 3 replicates per sample.
2010-07-14 | E-GEOD-22829 | biostudies-arrayexpress
Project description:Poly (ADP-ribose) glycohydrolase (PARG) is a dePARylating enzyme which promotes DNA repair by removal of poly (ADP-ribose) (PAR) from PARP1-parylated proteins. Loss or inhibition of PARG results in replication stress and sensitizes cancer cells to DNA damaging agents, suggesting that PARG inhibitors may provide a therapeutic option for cancer therapy. Indeed, PARG inhibitors (PARGi) are now undergoing clinical development for patients having tumors with homologous recombination deficiency (HRD), such as ovarian and breast cancer patients with germline or somatic BRCA1/2-mutations. Biomarkers of PARGi response will be required for the optimal development of these important new drugs. PARP inhibitors kill BRCA-deficient cancer cells by increasing ssDNA gaps during replication. Here, we report that, similar to PARP inhibitors, PARGi treatment can also cause an accumulation of ssGAPs in sensitive cells. PARGi exposure increased accumulation of S-Phase specific PAR, a marker for Okazaki fragment processing (OFP) defects on lagging strands, in sensitive cells but not in resistant cells. PARGi also caused accumulation of PAR at the replication fork and increased pRPA, a marker for replication stress, at the replication fork in sensitive cells. Additionally, PARGi exhibited monotherapy activity in some HR-deficient, as well as HR-proficient, patient-derived organoids of ovarian cancer, and drug sensitivity directly correlated with the accumulation of ssDNA gaps. Taken together, PARGi treatment results in toxic accumulation of PAR at replication forks resulting in ssDNA gaps due to OFP defects during replication. Regardless of the BRCA-status, the induction of ssDNA gaps in preclinical models of ovarian cancer cells correlates with PARGi sensitivity. Patient-derived organoids will be a useful model system for testing PARGi sensitivity and functional biomarkers
2024-10-31 | GSE270384 | GEO
Project description:Here we report our observations that have led us to propose that the transcription elongation factor NusA promotes a novel class of transcription-coupled repair (TCR) in addition to its previously proposed role in recruiting translesion synthesis (TLS) DNA polymerases to gaps encountered during transcription. Earlier we have reported that NusA physically and genetically interacts with the TLS DNA polymerase DinB (DNA pol IV). We find that Escherichia coli nusA11(ts) mutant strains, at the permissive temperature, are highly sensitive to nitrofurazone (NFZ) and 4-nitroquinolone-1-oxide but not to ultraviolet radiation. Gene expression profiling suggests this sensitivity is unlikely to be due to an indirect effect on gene expression affecting a known DNA repair or damage tolerance pathway. We demonstrate that an N2-furfuryl-dG (N2-f-dG) lesion, a structural analog of the principal lesion generated by NFZ, blocks transcription by E. coli RNA polymerase (RNAP) when present in the transcribed strand, but not when present in the non-transcribed strand. Our genetic analysis suggests that NusA participates in a nucleotide excision repair (NER)-dependent process to promote NFZ resistance. We provide evidence that transcription plays a role in the repair of NFZ-induced lesions through the isolation of RNAP mutants that display altered ability to survive NFZ exposure. We propose that NusA participates in a novel class of TCR involved in the identification and removal of a class of lesion, such as the N2-f-dG lesion, which are accurately and efficiently bypassed by DinB in addition to recruiting DinB for TLS at gaps encountered by RNAP.
2010-07-14 | GSE22829 | GEO
Project description:Single-stranded DNA (ssDNA) widely exists as intermediates in DNA metabolic pathways. The ssDNA binding protein, RPA, not only protects the integrity of ssDNA, but also directs the downstream factor that signals or repairs the ssDNA intermediate. However, it remains unclear how these enzymes/factors out-compete RPA and access to ssDNA. Using the budding yeast, Saccharomyces cerevisiae, as a model system, we discovered that Dna2, a key nuclease in DNA replication and repair, employs a bimodal interface to act with RPA both in cis and in trans. The cis-action renders RPA a processive unit for Dna2-catalyzed ssDNA digestion, where RPA actively delivers its bound ssDNA to Dna2. The trans-action mediated by an acidic patch from Dna2, on the other hand, enables Dna2 to operatie with a sub-optimal amount of RPA or to overcome DNA secondary structures. Genetically, this trans-action mode is not required for cell viability, but indispensable for successful DSB repair.
2022-02-22 | PXD028637 | Pride
Project description:We previously demonstrated that inactivation of the replication checkpoint via a mec1 mutation led to chromosome breakage at replication forks initiated from virtually all origins of replication, after transient exposure to hydroxyurea (HU), an inhibitor of ribonucleotide reductase. Furthermore, we have shown that chromosomes break at replication forks that have suffered single-stranded DNA (ssDNA) formation. Here we sought to determine whether all replication forks containing ssDNA gaps have equal probability of producing double strand breaks (DSBs) when cells attempt to recover from HU exposure. We devised a new methodology, Break-Seq, that combines our previously described DSB labeling with NextGen sequencing to map chromosome breaks with improved sensitivity and resolution. We show that DSBs preferentially occur at genes transcriptionally induced by HU. Notably, different subsets of the HU-induced genes produced DSBs in MEC1 and mec1 cells as replication forks traversed greater distance in MEC1 cells than in mec1 cells during the recovery from HU. Specifically, while MEC1 cells exhibited chromosome breakage at stress-response transcription factors, mec1 cells predominantly suffered chromosome breakage at transporter genes, many of which are the substrates of the said transcription factors. We propose that HU-induced chromosome fragility arises at higher frequency near HU-induced genes as a result of destabilized replication forks encountering transcription factor binding and/or the act of transcription. Our model provides an explanation for a long-standing problem in chromosome biology: why different replication inhibitors produce different spectra of chromosome breakage? We propose that different inhibitors elicit different transcription responses as well as destabilize replication forks, and, when the two processes collide, ssDNA at the replication fork suffers further strand breakage, causing DSBs.
2015-01-12 | GSE58808 | GEO
Project description:We have developed a method to analyze single-stranded DNA (ssDNA) formation on a genomic scale by using microarrays. Using this technique we have assessed the location and the amount of ssDNA in S. cerevisiae during DNA replication. We have observed that when replication is impeded by hydroxyurea, ssDNA formation can be detected in both wild type and the checkpoint-deficient rad53 cells. However, while wild type cells showed ssDNA formation at only a subset of origins, rad53 cells formed ssDNA at virtually all known origins. Moreover, in rad53 cells the ssDNA regions did not expand over time, presumably due to collapsed replication forks. We also applied this method to map origins in S. pombe, taking advantage of the conserved replication checkpoint function by Cds1, the homolog of Rad53 in S. pombe. Keywords: ssDNA, HU, replication, time course
2006-01-30 | GSE4099 | GEO
Project description:We previously demonstrated that inactivation of the replication checkpoint via a mec1 mutation led to chromosome breakage at replication forks initiated from virtually all origins of replication, after transient exposure to hydroxyurea (HU), an inhibitor of ribonucleotide reductase. Furthermore, we have shown that chromosomes break at replication forks that have suffered single-stranded DNA (ssDNA) formation. Here we sought to determine whether all replication forks containing ssDNA gaps have equal probability of producing double strand breaks (DSBs) when cells attempt to recover from HU exposure. We devised a new methodology, Break-Seq, that combines our previously described DSB labeling with NextGen sequencing to map chromosome breaks with improved sensitivity and resolution. We show that DSBs preferentially occur at genes transcriptionally induced by HU. Notably, different subsets of the HU-induced genes produced DSBs in MEC1 and mec1 cells as replication forks traversed greater distance in MEC1 cells than in mec1 cells during the recovery from HU. Specifically, while MEC1 cells exhibited chromosome breakage at stress-response transcription factors, mec1 cells predominantly suffered chromosome breakage at transporter genes, many of which are the substrates of the said transcription factors. We propose that HU-induced chromosome fragility arises at higher frequency near HU-induced genes as a result of destabilized replication forks encountering transcription factor binding and/or the act of transcription. Our model provides an explanation for a long-standing problem in chromosome biology: why different replication inhibitors produce different spectra of chromosome breakage? We propose that different inhibitors elicit different transcription responses as well as destabilize replication forks, and, when the two processes collide, ssDNA at the replication fork suffers further strand breakage, causing DSBs.
2015-01-12 | GSE63516 | GEO
Project description:Translesion DNA synthesis (TLS) is a cellular process that enables the bypass of DNA lesions encountered during DNA replication and is emerging as a primary target of chemotherapy. Among vertebrate DNA polymerases, polymerase kappa (PolK) has the distinctive ability to bypass minor groove DNA adducts in vitro. However, PolK is also required for cells to overcome major groove DNA adducts but the basis of this requirement is unclear. Here, we combine CRISPR base editor screening technology in human cells with TLS analysis of defined DNA lesions in Xenopus egg extracts to unravel the functions and regulations of PolK during lesion bypass. Strikingly, we show that PolK has two main functions during TLS, which are differentially regulated via Rev1 binding. On the one hand, PolK is essential to replicate across a minor groove DNA lesion in a process that depends on PCNA ubiquitylation but is independent of Rev1. On the other hand, via its cooperative interaction with Rev1 and ubiquitylated PCNA, PolK appears to stabilize the Rev1-PolZ extension complex on DNA to allow extension past major groove DNA lesions and abasic sites, in a process that is independent of PolK's catalytic activity. Together, our work identifies catalytic and non-catalytic functions of PolK in TLS and reveals important regulatory mechanisms underlying the unique domain architecture present at the C-terminal end of Y-family TLS polymerases.
2024-08-27 | PXD044258 | Pride