Mapping polymerase usage by tracking ribonucleotide incorporation (HydEn-seq) during DNA replication
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ABSTRACT:
ORGANISM(S): Schizosaccharomyces pombe Saccharomyces cerevisiae
PROVIDER: GSE125855 | GEO | 2019/01/30
REPOSITORIES: GEO
Similar Datasets
Project description:Multiple DNA polymerases are needed to replicate genetic information. Here we describe the use of ribonucleotide incorporation as a biomarker of replication enzymology in vivo. We find that ribonucleotides are incorporated into the yeast nuclear genome in replicase specific and strand-specific patterns that identify replication origins and where polymerase switching occurs. Ribonucleotide density varies across the genome as a function of the replicase, base, local sequence and proximity to nucleosomes and transcription start sites. Ribonucleotides are present in one strand at high densityat mitochondrial replication origins, implying unidirectional replication of a circular genome. The evolutionary conservation of the enzymes that incorporate and process ribonucleotides in DNA suggests that the use of ribonucleotides as biomarkers of DNA synthesis in cells will have widespread applicability. Mapping genomic ribonucleotides in 14 Saccharomyces cerevisiae strains (seven DNA polymerase backgrounds, with or without RNH201), via HydEn-seq (end sequencing of genomic fragments generated by alkaline hydrolysis).
2015-01-26 | E-GEOD-62181 | biostudies-arrayexpress
Project description:Multiple DNA polymerases are needed to replicate genetic information. Here we describe the use of ribonucleotide incorporation as a biomarker of replication enzymology in vivo. We find that ribonucleotides are incorporated into the yeast nuclear genome in replicase specific and strand-specific patterns that identify replication origins and where polymerase switching occurs. Ribonucleotide density varies across the genome as a function of the replicase, base, local sequence and proximity to nucleosomes and transcription start sites. Ribonucleotides are present in one strand at high densityat mitochondrial replication origins, implying unidirectional replication of a circular genome. The evolutionary conservation of the enzymes that incorporate and process ribonucleotides in DNA suggests that the use of ribonucleotides as biomarkers of DNA synthesis in cells will have widespread applicability.
2015-01-26 | GSE62181 | GEO
Project description:Mapping polymerase usage by tracking ribonucleotide incorporation (HydEn-seq) during DNA replication
| PRJNA517710 | ENA
Project description:Previous work has demonstrated the presence of ribonucleotides in human mitochondrial DNA (mtDNA) and in the present study we use a genome-wide approach to precisely map the location of these. We find that ribonucleotides are distributed evenly between the heavy- and light-strand of mtDNA. The relative levels of incorporated ribonucleotides reflect that DNA polymerase γ discriminates the four ribonucleotides differentially during DNA synthesis. The observed pattern is also dependent on the mitochondrial deoxyribonucleotide (dNTP) pools and disease-causing mutations that change these pools alter both the absolute and relative levels of incorporated ribonucleotides. Our analyses strongly suggest that DNA polymerase γ-dependent incorporation is the main source of ribonucleotides in mtDNA and argues against the existence of a mitochondrial ribonucleotide excision repair pathway in human cells. Furthermore, we clearly demonstrate that when dNTP pools are limiting, ribonucleotides serve as a source of building blocks to maintain DNA replication and genome stability. Increased levels of embedded ribonucleotides in patient cells with disturbed nucleotide pools may constitute to a pathogenic mechanism that affects mtDNA stability and impair new rounds of mtDNA replication
2017-02-13 | GSE90054 | GEO
Project description:We have established a novel sequencing approach to characterise usage of replicative DNA polymerases in S. pombe. This approach allows us to determine the roles of DNA polymerase delta and epsilon in lagging strand and leading strand DNA synthesis, respectively in genome-wide scale. Utilising the dataset of usage of these polymerases, we also successfully identified DNA replication initiation sites at high resolution. Furthermore, our informatics analysis establishes genome-wide datasets of fork direction rates, replication timing and the probability of replication termination. We mapped ribonucleotide-incorporation by the mutated DNA polymerase delta and epsilon at single-nucleotide resolution and subsequent informatics analysis was performed to generate datasets listed here.
2015-02-03 | E-GEOD-62108 | biostudies-arrayexpress
Project description:Ribonucleotides are frequently incorporated into DNA during replication in eukaryotes. Here we map genome-wide distribution of these ribonucleotides as markers of replication enzymology in budding yeast, using a new 5' DNA end-mapping method, hydrolytic end sequencing (HydEn-seq). HydEn-seq of DNA from ribonucleotide excision repair-deficient strains reveals replicase- and strand-specific patterns of ribonucleotides in the nuclear genome. These patterns support the roles of DNA polymerases ? and ? in lagging-strand replication and of DNA polymerase ? in leading-strand replication. They identify replication origins, termination zones and variations in ribonucleotide incorporation frequency across the genome that exceed three orders of magnitude. HydEn-seq also reveals strand-specific 5' DNA ends at mitochondrial replication origins, thus suggesting unidirectional replication of a circular genome. Given the conservation of enzymes that incorporate and process ribonucleotides in DNA, HydEn-seq can be used to track replication enzymology in other organisms.
| S-EPMC4351163 | biostudies-literature
Project description:All DNA polymerases misincorporate ribonucleotides despite their preference for deoxyribonucleotides, and analysis of cultured cells indicates that mammalian mitochondrial DNA (mtDNA) tolerates such replication errors. However, it is not clear to what extent ribonucleotides are incorporated into the mtDNA of solid tissues, or whether they might play a role in human pathologies. Here, we show the DNA in mitochondria of solid tissues contains many more embedded ribonucleotides than that of cultured cells, consistent with the former’s high ratio of ribonucleotide to deoxynucleotide triphosphates and that rAMPs are the predominant ribosubstitution events. This pattern changes in a mouse model of Mpv17 deficiency, as rGMPs are the major embedded ribonucleotides of mtDNA. However, while mitochondrial dGTP is reduced in the liver of the KO mice, the brain shows no change in the overall dGTP pool, leading us to infer that Mpv17 determines the local concentration or quality of dGTP. Embedded rGMPs are expected to impede DNA replication more than other rNMPs, and elevated rGMP incorporation is associated with early-onset mtDNA depletion in liver and late-onset multiple deletions in brain of the Mpv17 ablated mice. These findings suggest that aberrant ribonucleotide incorporation is a primary mtDNA abnormality that can result in pathology.
2017-10-23 | GSE103429 | GEO
Project description:Ribonucleotide excision repair prevents intestinal tumorigenesis
| PRJNA436583 | ENA
Project description:Deregulated expression of MYC enhances glutamine utilization and renders cell survival dependent on glutamine, inducing “glutamine addiction”. Surprisingly, colon cancer cells that express high levels of MYC due to WNT pathway mutations, are not glutamine-addicted but undergo a reversible cell cycle arrest upon glutamine deprivation. We show here that glutamine deprivation suppresses translation of endogenous MYC via the 3’-UTR of the MYC mRNA, enabling escape from apoptosis. This regulation is mediated by glutamine-dependent changes in adenosine nucleotide levels. Glutamine deprivation causes a global reduction in promoter association of RNA Polymerase II (RNAPII) and slows transcriptional elongation. While activation of MYC restores binding of MYC and RNAPII function on most promoters, restoration of elongation is imperfect and activation of MYC in the absence of glutamine causes stalling of RNAPII on multiple genes, correlating with R-loop formation. Stalling of RNAPII and R-loop formation can cause DNA damage, arguing that the MYC 3’-UTR is critical for maintaining genome stability when ribonucleotide levels are low.
2022-02-28 | PXD005829 | Pride
Project description:Insufficient repair of DNA lesions results in the acquisition of somatic mutations and displays the driving force in cancerogenesis. Ribonucleotide incorporation by eukaryotic DNA polymerases occurs during every round of genome duplication and represents by far the most frequent type of naturally occurring DNA lesions. RNAse H2 removes misincorporated ribonucleotides from genomic DNA in a process termed ribonucleotide excision repair (RER). Whether intestinal epithelial proliferation requires RER and whether abrogation of RER is involved in the etiology of cancerogenesis at all is unknown. Mice with an epithelial specific deletion of RNase H2 subunit b (H2bΔIEC) and co-deletion of the tumor suppressor p53 (H2b/p53ΔIEC) were generated and phenotyped at young and old age. RNA sequencing was performed in isolated epithelial cells and intestinal organoids. Mutational signature of spontaneous tumors from H2b/p53ΔIEC mice were characterized using exome sequencing. Association of tumor RNase H2 expression and patient survival was assessed in transcriptome data from 467 CRC patients. H2bΔIEC mice display chronic epithelial DNA damage and develop a p53-dependent proliferative exhaustion of the intestinal stem cell compartment. H2b/p53ΔIEC mice have restored epithelial proliferation and spontaneously develop small intestinal carcinomas. Resulting tumors display a distinct mutational signature characterized by T>G base substitutions at GpTpG trinucleotides. Transcriptome data from human colorectal cancer patients indicate that reduced RNase H2 expression is associated with poor survival in CRC. Conclusion: We propose a hitherto unappreciated role for RNase H2 as a tumor suppressor gene in CRC. Our mouse model provides a novel tool to study the impact of abrogated RER on intestinal carcinogenesis.
2018-10-01 | GSE111318 | GEO