A global profile of replication polymerase usage
Ontology highlight
ABSTRACT:
ORGANISM(S): Schizosaccharomyces pombe
PROVIDER: GSE62108 | GEO | 2015/02/03
SECONDARY ACCESSION(S): PRJNA263280
REPOSITORIES: GEO
Similar Datasets
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:Faithful duplication of DNA is essential for the maintenance of genomic stability in all organisms. DNA synthesis proceeds bi-directionally with continuous synthesis of leading strand DNA and discontinuous synthesis of lagging strand DNA. Herein, we describe a method of enriching and Sequencing of Protein-Associated Nascent strand DNA (eSPAN) to detect whether a protein binds the leading- and lagging-strands of DNA replication forks. We show that Pol-epsilon, PCNA, Cdc45, Mcm6 and Mcm10 preferentially associate with leading strands, whereas Pol-alpha, Pol32, Pol-delta, Rfa1 and Rfc1 associate with lagging strands of hydroxyurea (HU)-stalled replication forks. In contrast, PCNA is enriched at lagging strands of normal replication forks in wild type cells and HU-stalled forks in cells lacking Elg1. These studies demonstrate a strategy to reveal proteins at leading and lagging strands of DNA replication forks, and suggest that the unloading of PCNA from lagging strands of HU-stalled replication forks helps maintain genome integrity.
2014-10-29 | GSE52614 | GEO
Project description:Chromatin replication is intricately intertwined with DNA replication, and the recycling of parental histones is essential for epigenetic inheritance. The transfer of parental histones to both the DNA replication leading and lagging strands involves two distinct pathways: the leading strand utilizes DNA polymerase ε subunits Dpb3/Dpb4, while the lagging strand is facilitated by the MCM helicase subunit Mcm2. However, the process by which Mcm2, moving along the leading strand, facilitates the transfer of parental histones to the lagging strand remains unclear. Our study reveals that the deletion of Pol32, a non-essential subunit of major lagging-strand DNA polymerase δ, results in a predominant transfer of parental histone H3-H4 to the replication leading strand. Biochemical analyses further demonstrate that Pol32 can bind histone H3-H4 both in vivo and in vitro. The interaction of Pol32 with parental histone H3-H4 is disrupted by the mutation of Mcm2's histone H3-H4 binding domain. In conclusion, our findings identify the DNA polymerase delta subunit Pol32 as a novel key histone chaperone downstream of Mcm2, mediating the transfer of parental histones to the lagging strand during DNA replication.
2024-04-24 | GSE252049 | GEO
Project description:The division of labour between DNA polymerase underlies the accuracy and efficiency of replication. However, the roles of replicative polymerases have not been directly established in human cells. We developed polymerase usage sequence (Pu-seq) in HCT116 cells and mapped Polε and Polα usage genome wide. The polymerase usage profiles show Polε synthesises the leading strand and Polα contributes mainly to lagging strand synthesis. Combining the Polε and Polα profiles, we accurately predict the genome-wide pattern of fork directionality, plus zones of replication initiation and termination. We confirm that transcriptional activity contributes toshapes the patterns of initiation and termination and, by separately analysing the effect of transcription ofon both both co-directional and converging forks, demonstrate that coupled DNA synthesis of leading and lagging strands in both co-directional and convergent forks is compromised by transcription. Polymerase uncoupling is particularly evident in the vicinity of large genes, including the two most unstable common fragile sites, FRA3B and FRA3D, thus linking transcription-induced polymerase uncoupling to chromosomal instability.
2022-11-02 | GSE189668 | GEO
Project description:During every cell cycle, both the genome and the associated chromatin must be accurately replicated. Chromatin Assembly Factor-1 (CAF-1) is a key regulator of chromatin replication, but how CAF-1 functions in relation to the DNA replication machinery is unknown. Here, we reveal that this crosstalk differs between the leading and lagging strand at replication forks. Using biochemical reconstitution, we show that DNA and histones promote CAF-1 recruitment to its binding partner PCNA and reveal that two CAF-1 complexes are required for efficient nucleosome assembly under these conditions. Remarkably, in the context of the replisome, CAF-1 competes with the leading strand DNA polymerase epsilon (Pole) for PCNA binding. However, CAF-1 does not affect the activity of the lagging strand DNA polymerase Delta (Pold). Yet, in cells, CAF-1 deposits newly synthesized histones equally on both daughter strands. Thus, on the leading strand, chromatin assembly by CAF-1 cannot occur simultaneously to DNA synthesis, while on the lagging strand these processes may be coupled. We propose that these differences may facilitate distinct parental histone recycling mechanisms and accommodate the inherent asymmetry of DNA replication.
2023-08-08 | GSE223782 | GEO
Project description:Faithful duplication of DNA is essential for the maintenance of genomic stability in all organisms. DNA synthesis proceeds bi-directionally with continuous synthesis of leading strand DNA and discontinuous synthesis of lagging strand DNA. Herein, we describe a method of enriching and Sequencing of Protein-Associated Nascent strand DNA (eSPAN) to detect whether a protein binds the leading- and lagging-strands of DNA replication forks. We show that Pol-epsilon, PCNA, Cdc45, Mcm6 and Mcm10 preferentially associate with leading strands, whereas Pol-alpha, Pol32, Pol-delta, Rfa1 and Rfc1 associate with lagging strands of hydroxyurea (HU)-stalled replication forks. In contrast, PCNA is enriched at lagging strands of normal replication forks in wild type cells and HU-stalled forks in cells lacking Elg1. These studies demonstrate a strategy to reveal proteins at leading and lagging strands of DNA replication forks, and suggest that the unloading of PCNA from lagging strands of HU-stalled replication forks helps maintain genome integrity. We synchronized yeast cells at G1 and released into early S phase in the presence of BrdU, a nucleotide analog that can be incorporated into newly synthesized DNA strand, and hydroxyurea (HU), a ribonucleotide reductase inhibitor. HU has no effect on initiation of DNA replication at early replication origins, but inhibit late replication firing. In addition, replication forks are stalled due to depletion of dNTPs. We then performed chromatin-immunoprecipitation of 12 proteins of interest following a standard procedure. Protein-bound DNAs were then reverse-crosslinked and double strand DNA was denatured. Nascent DNA was enriched by immunoprecipitation using anti-BrdU antibodies. The recovered ssDNA was first marked with ligation to one oligo at 3M-bM-^@M-^Y end before conversion to dsDNA for library preparation and sequencing. In this way, the directionality of ssDNA and therefore strand information of each sequenced DNA were known. The sequencing tag was mapped to both Watson (red) and Crick (blue) strands of the reference genome. In addition to ChIP-eSPAN, we also performed BrdU-IP and single strand DNA sequence (BrdU-ssSeq) and protein ChIP followed by single-strand DNA sequencing (ChIP-ssSeq) for each corresponding ChIP-eSPAN experiment. We also performed Mcm4 and Mcm6 ChIP-seq using cells synchronized at G1 phase of the cell cycle for identification of replication origins in comparison with published dataset. Some protein ChIP-ssSeq and ChIP-eSPAN experiments were repeated and the data fits well each other. Therefore, we did not repeat all protein ChIP-ssSeq and ChIP-eSPAN experiments.
2014-10-29 | E-GEOD-52614 | biostudies-arrayexpress
Project description:In response to DNA replication stress, DNA replication checkpoint is activated to maintain fork stability, a process critical for maintenance of genome stability. However, how DNA replication checkpoint regulates replication forks remain elusive. Here we show that Rad53, a highly conserved replication checkpoint kinase, functions to couple leading and lagging strand DNA synthesis. In wild type cells under HU induced replication stress, synthesis of lagging strand, which contains ssDNA gaps, is comparable to leading strand DNA. In contrast, synthesis of lagging strand is much more than leading strand, and consequently, leading template ssDNA coated with ssDNA binding protein RPA was detected in rad53-1 mutant cells, suggesting that synthesis of leading strand and lagging strand DNA is uncoupled. Mechanistically, we show that replicative helicase MCM and leading strand DNA polymerase Pole move beyond actual DNA synthesis and that an increase in dNTP pools largely suppresses the uncoupled leading and lagging strand DNA synthesis. Our studies reveal an unexpected mechanism whereby Rad53 regulates replication fork stability.
2018-02-11 | GSE89721 | GEO
Project description:The tolerance pathway allows bypassing deleterious lesions that block replicative DNA polymerases. In eukaryotes tolerance is controlled by ubiquitylation of the DNA replication factor PCNA4. Here, we show that PCNAK164-ubiquitin proteases (PCNA-DUBs) Ubp10 and Ubp12 localise to replication forks. In particular, the main PCNA-DUB, Ubp10, associates primarily to nascent lagging strands. We also found that cells deficient for PCNA deubiquitylation show both increased interaction of TLS polymerase ζ-associated Rev1 with lagging strands and Rad52-dependent template switching events. This evidence reveals a fork-coupled layer of DDT regulation allowing strand-specific pathway choices.
2019-10-29 | GSE90157 | GEO
Project description:Publication abstract: Telomeres, the protective ends of eukaryotic chromosomes, are replicated through concerted actions by conventional DNA polymerases and telomerase, though the regulation of this process is not fully understood. Telomere replication requires (C)-Stn1-Ten1, a telomere ssDNA-binding complex that is homologous to RPA. Here, we show that the evolutionarily conserved phosphatase Ssu72 is responsible for terminating the cycle of telomere replication in fission yeast. Ssu72 controls the recruitment of Stn1 to telomeres by regulating Stn1 phosphorylation at S74, a residue that lies within the conserved OB fold domain. Consequently, ssu72Δ mutants are defective in telomere replication and exhibit long 3′ overhangs, which are indicative of defective lagging strand DNA synthesis. We also show that hSSU72 regulates telomerase activation in human cells by controlling the recruitment of hSTN1 to telomeres. Thus, in this study, we demonstrate a previously unknown yet conserved role for the phosphatase SSU72, whereby this enzyme controls telomere homeostasis by activating lagging strand DNA synthesis, thus terminating the cycle of telomere replication. Summary of MS experiment: Stn1 protein was tagged in the C-terminus with 13-myc tag and purified by immunoprecipitation. The purified extracts were separated by SDS-PAGE and proteins between 63 and 75 kDa were excised and in-gel digested. Tryptic peptides were analyzed by LC-MS/MS using an AB Sciex TripleTOF 6600 mass spectrometer upon separation by nanoLC-MS using an Ekspert 425 nanoLC with cHiPLC. Stn1 protein was identified with 48% of coverage and Serine-74 was found to be phosphorylated.
2019-02-19 | PXD011953 | Pride
Project description:In higher eukaryotes, repetitive DNA sequences are transcriptionally silenced through histone H3 lysine 9 tri-methylation (H3K9me3). A loss of silencing of these elements leads to genome instability and human diseases, including cancer and aging1-3. While the role of H3K9me3 in the establishment and maintenance of heterochromatin and repression of DNA repeats has been extensively studied4-6, the pattern and mechanism underlying the partitioning of H3K9me3 at replicating DNA strands were unknown. Here, we report that H3K9me3 is preferentially transferred onto the leading strands of replication forks, which occurs predominantly at Long Interspersed Nuclear Element (LINE) retrotransposons that are theoretically transcribed at the head-on direction with replication fork movement. In contrast, all other modified forms of histones tested are distributed in a nearly symmetric manner at the leading and lagging strands. Mechanistically, the Human Silencing Hub (HUSH) complex interacts with the leading strand DNA polymerase Pol ε, and contributes to the asymmetric segregation of H3K9me3 during chromatin replication. Cells deficient for Pol ε (POLE3 and POLE4), the HUSH complex (MPP8 and TASOR), or cells expressing a MPP8 mutant defective of H3K9me3 binding, or TASOR mutants with reduced interaction with Pol ε, show compromised H3K9me3 asymmetry and increased LINE expression. These results reveal an unexpected mechanism whereby the HUSH complex functions with Pol ε to promote asymmetric H3K9me3 distribution at LINEs to suppress their expression during S phase.
2023-08-17 | GSE211192 | GEO