Control of DNA replication fork speed
Ontology highlight
ABSTRACT:
PROVIDER: PRJEB86591 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Intracellular levels of deoxyribonucleoside triphosphate (dNTP) must be tightly regulated to preserve genome integrity. Indeed, alterations in dNTP pools have recently been associated with increased mutagenesis, genomic instability and tumorigenesis. However, the mechanisms by which low or imbalanced dNTP pools affect DNA replication remain poorly understood. Here, we have modulated the activity of ribonucleotide reductase (RNR), a key enzyme catalyzing a rate-limiting step of dNTP production, to monitor the effect of altered dNTP levels on replication dynamics in budding yeast. We show that dNTP pools are limiting for normal DNA synthesis as upregulation of RNR activity increases replication fork speed. In contrast, inhibition of RNR activity with hydroxyurea (HU) induces a sharp transition from a regular- to a slow-replication mode within minutes after S-phase entry. Interestingly, we found that upregulation of RNR activity delays this transition and that dNTP levels modulate both fork speed and origin usage under replication stress. Moreover, we report that chromosomal instability (CIN) mutants show increased dNTP pools and enhanced DNA synthesis in the presence of HU. Since upregulation of RNR allows forks to progress faster in the presence of DNA lesions, we propose that CIN mutants adapt to chronic replication stress by upregulating dNTP pools.
2012-01-01 | GSE33686 | GEO
Project description:Analysis of topoisomerase function in bacterial replication fork movement: use of DNA microarrays. We used DNA microarrays of the Escherichia coli genome to trace the progression of chromosomal replication forks in synchronized cells. We found that both DNA gyrase and topoisomerase IV (topo IV) promote replication fork progression. When both enzymes were inhibited, the replication fork stopped rapidly. The elongation rate with topo IV alone was 1/3 of normal. Genetic data confirmed and extended these results. Inactivation of gyrase alone caused a slow stop of replication. Topo IV activity was sufficient to prevent accumulation of (+) supercoils in plasmid DNA in vivo, suggesting that topo IV can promote replication by removing (+) supercoils in front of the chromosomal fork. This study is detailed in Khodursky AB et al.(2000) Proc Natl Acad Sci U S A 97:9419-24 Keywords: other
2001-07-30 | E-GEOD-8 | biostudies-arrayexpress
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
2024-12-18 | GSE254199 | GEO
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
2024-12-18 | GSE254196 | GEO
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
2024-12-18 | GSE254195 | GEO
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
2024-12-18 | GSE281980 | GEO
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
2024-12-18 | GSE254535 | GEO
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
2024-12-18 | GSE254534 | GEO
Project description:Safeguarding replication fork stability in transcriptionally active regions, which require high DNA replication accuracy, is crucial for precise DNA replication and prevention of mutations. However, how cells ensure the stability of replication forks in these regions remains a critical challenge. Here, we discovered the pervasive existence of replication forks-associated RNA-DNA hybrids (RF-RDs) within transcriptionally active regions, where they act as a protective barrier against DNA2-mediated nascent DNA degradation and prevent replication fork collapse upon replication stress. Subsequently, the RNA helicase DDX39A dismantles RF-RDs, facilitating proper DNA2-mediated DNA resection and replication fork restart. Excessive dissolution of RF-RDs causes replication fork collapse and genomic instability, while insufficient dissolution of RF-RDs under replication stress increases fork stability, resulting in chemoresistance that can be reversed by eliminating RF-RDs. In summary, we elucidated the prevalence of RF-RDs at replication forks within transcriptionally active regions, revealed their pivotal role in safeguarding replication fork stability, and proposed that targeting RF-RDs holds promise for augmenting chemotherapeutic efficacy.
2024-12-18 | GSE254306 | GEO
Project description:The germinal center (GC) is a microanatomical compartment wherein high-affinity antibody-producing B cells are selectively expanded. B cells proliferate and mutate their antibody genes in the dark zone (DZ) of the GC and are then selected by T cells in the light zone (LZ) on the basis of affinity. Here, we show that T cell help regulates the speed of cell cycle phase transitions and DNA replication of GC B cells. Genome sequencing and single-molecule analyses revealed that T cell help shortens S phase by regulating replication fork progression while preserving the relative order of replication origin activation. Thus, high-affinity GC B cells are selected by a mechanism that involves prolonged dwell time in the DZ where selected cells undergo accelerated cell cycles. To determine whether GC B cells receiving high levels of T cell help show a specific change in gene expression, we compared DZ cells in the G1 phase of the cell cycle from αDEC-OVA and control αDEC-CS treated GCs using a fluorescent ubiquitination-based cell cycle indicator (Fucci-tg). RNA sequencing revealed that T cell-mediated selection produced an increase in gene expression programs associated with the cell cycle, metabolism, including the metabolism of nucleotides, and genes downstream of c-Myc and the E2F transcription factors.
2015-08-12 | E-GEOD-71295 | biostudies-arrayexpress