Mus musculus
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA324723 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR3645468_1.fastq.gz | Fastqsanger.gz | |||
| SRR3645468_2.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 2 of 2 |
Similar Datasets
Project description:DNA polymerase theta (Pol-theta)-mediated end-joining (TMEJ) repairs DNA double-strand breaks and confers resistance to genotoxic agents. How Pol-theta is regulated at the molecular level to exert TMEJ remains unknown. We find that Pol-theta interacts with and is PARylated by PARP1 in vitro and in cells. PARP1 recruits Pol-theta to the vicinity of DNA damage via PARylation dependent liquid demixing, however, PARylated Pol-theta (PAR-Pol-theta) cannot perform TMEJ due to its inability to bind DNA. PARG-mediated de-PARylation of Pol-theta reactivates its DNA binding and end-joining activities in vitro. Consistent with this, PARG is essential for TMEJ in cells and the temporal recruitment of PARG to DNA damage corresponds with TMEJ activation and dissipation of PARP1 and PAR. These studies support a two-step spatiotemporal mechanism of TMEJ regulation. First, PARP1 PARylates Pol-theta and facilitates its recruitment to DNA damage sites in an inactivated state. PARG subsequently activates TMEJ by removing repressive PAR marks on Pol-theta.
| MSV000092839 | MassIVE
Project description:In homologous recombination deficient cells, polymerase theta (Pol θ)-mediated end-joining (TMEJ) repairs replicative DNA breaks during mitosis through interactions with RHINO and TOPBP1. V(D)J recombination and class switch recombination (CSR) rely on DNA breakage in G1-phase B lymphocytes and repair by non-homologous end-joining (NHEJ). In this study, we assayed CSR in primary B cells deficient in XRCC4, SHLD1, and Pol θ. We found that B cells deficient in both XRCC4 and Pol θ, or SHLD1 and Pol θ, exhibit an increased rate of IgH breaks, while retaining CSR levels similar to those of B cells deficient in XRCC4 or SHLD1. We show that in XRCC4- or SHLD1-deficient B cells, Pol θ promotes the formation of aberrant recombination products characterized by exacerbated double-strand break (DSB) end resection, inversion and microhomology, and that these end-joining events occur independently of RHINO. Furthermore, we find that TMEJ of RAG-generated DSBs is also independent of RHINO and concomitant to S/G2 entry. Based on these results, we propose that in the absence of NHEJ, TMEJ repairs persistent G1-phase DSBs in S/G2, rather than in mitosis.
2025-08-26 | GSE306291 | GEO
Project description:Polymerase theta-mediated end-joining repairs persistent G1-induced DNA breaks in S/G2.
| PRJNA1310422 | ENA
Project description:Genetic Determinants of Cellular Addiction to DNA Polymerase Theta
| PRJNA556352 | ENA
Project description:Replication stress, if not effectively and timely addressed, could result in DNA damage in mitosis. However, it remains unknown the relationship between mitotic DNA damage and other mitotic events such as nuclear envelope (NE) breakdown and reassembly. Here we report that replication stress could generate NE rupture. Rather than de novo formation, the rupture per se is a result of nuclear envelope reassembly defect (NERD) in mitosis. Repair of mitotic DNA damage by DNA polymerase theta (Polθ), a key microhomology-mediated end joining (MMEJ) factor, suppresses NERD. Furthermore, exacerbated NERD is observed in multiple conditions of synthetic lethality, suggesting NERD might be a general consequence of synthetic lethality. In addition, genomic mapping of LADs identifies a population of RESS-LADs (replication stress-sensitive LADs). Replication stress causes the loss of CFSs at RESS-LADs, likely due to the sustained phosphorylation of Lamin A/C at the NE rupture sites. Altogether, our findings establish a novel link between replication stress-induced genome instability and nuclear vulnerability.
2025-08-16 | GSE271990 | GEO
Project description:By covalently linking Watson and Crick strands, DNA interstrand crosslinks (ICLs) are highly toxic lesions that block DNA replication and threaten genome integrity. The Fanconi anemia (FA) pathway orchestrates ICL repair during DNA replication, with ubiquitylated FANCI-FANCD2 (ID2) marking the activation step that triggers incisions on one DNA strand to unhook the ICL. ICL unhooking generates a two-ended double-strand break (DSB) on one of the daughter molecules, while leaving a gap comprising the ICL-adduct on the other. Restoration of the adducted molecule by DNA polymerase zeta-mediated translesion synthesis (TLS) creates a template required for repair of the DSB via homologous recombination (HR), but how these processes are coordinated to ensure faithful ICL repair is not known. Here, we uncover a crucial role for SCAI in promoting ICL repair downstream of ID2 activation. Using Xenopus egg extracts and human cells, we show that SCAI forms a complex with DNA polymerase zeta and localizes to ICLs during DNA replication. SCAI-deficient cells are exquisitely sensitive to ICL-inducing drugs and display principal hallmarks of FA gene inactivation, including broken and radial chromosome accumulation. In the absence of SCAI, DSB intermediates are preferentially re-ligated by illegitimate DNA polymerase theta-dependent microhomology-mediated end-joining (MMEJ). Consistently, the hypersensitivity of SCAI-deficient cells to ICLs can be reverted by suppressing FA pathway activation. Our work establishes SCAI as a critical mediator of ICL resolution via the FA pathway, acting at the interphase of the TLS and HR steps to prevent erroneous repair and chromosomal instability.
2022-02-18 | PXD024280 | Pride
Project description:By covalently linking Watson and Crick strands, DNA interstrand crosslinks (ICLs) are highly toxic lesions that block DNA replication and threaten genome integrity. The Fanconi anemia (FA) pathway orchestrates ICL repair during DNA replication, with ubiquitylated FANCI-FANCD2 (ID2) marking the activation step that triggers incisions on one DNA strand to unhook the ICL. ICL unhooking generates a two-ended double-strand break (DSB) on one of the daughter molecules, while leaving a gap comprising the ICL-adduct on the other. Restoration of the adducted molecule by DNA polymerase zeta-mediated translesion synthesis (TLS) creates a template required for repair of the DSB via homologous recombination (HR), but how these processes are coordinated to ensure faithful ICL repair is not known. Here, we uncover a crucial role for SCAI in promoting ICL repair downstream of ID2 activation. Using Xenopus egg extracts and human cells, we show that SCAI forms a complex with DNA polymerase zeta and localizes to ICLs during DNA replication. SCAI-deficient cells are exquisitely sensitive to ICL-inducing drugs and display principal hallmarks of FA gene inactivation, including broken and radial chromosome accumulation. In the absence of SCAI, DSB intermediates are preferentially re-ligated by illegitimate DNA polymerase theta-dependent microhomology-mediated end-joining (MMEJ). Consistently, the hypersensitivity of SCAI-deficient cells to ICLs can be reverted by suppressing FA pathway activation. Our work establishes SCAI as a critical mediator of ICL resolution via the FA pathway, acting at the interphase of the TLS and HR steps to prevent erroneous repair and chromosomal instability.
2022-02-18 | PXD029409 | Pride
Project description:SPO11-promoted DNA double-strand breaks (DSBs) formation is a crucial step for meiotic recombination, and it is indispensable to detect the broken DNA ends accurately for dissecting the molecular mechanisms behind. Here, we report a novel technique, named DEtail-seq (DNA End tailing followed by sequencing), that can directly and quantitatively capture the meiotic DSB 3’ overhang hotspots at single-nucleotide resolution.
2023-01-08 | GSE154289 | GEO
Project description:Two DNA repair pathways, non-homologous end joining (NHEJ) and alternative end joining (A-EJ), are involved in V(D)J recombination and chromosome translocation. Previous studies reported distinct repair mechanisms for chromosome translocation, with NHEJ predominantly involved in human and A-EJ in mice. NHEJ depends on DNA-PKcs, a critical partner in synapsis formation and downstream component activation. While DNA-PKcs inhibition promotes chromosome translocations harboring microhomologies in mice, its synonymous effect in human is not known. We find partial DNA-PKcs inhibition in human cell lines leads to increased genome-wide translocations composed mostly of direct joints, indicating the continued involvement of dampened NHEJ in these processes. In contrast, complete DNA-PKcs inhibition and genetic inhibition DNA-PKcs kinase domain substantially increased microhomology-mediated end joining (MMEJ), thus bridging the two different translocation mechanisms between human and mice. Similar to a previous study on Ku70 deletion, DNA-PKcs deletion in G1/G0-phase mouse pro-B cell lines, impair the recombination of RAG1/2-mediated DNA double-strand breaks (DSBs). This DNA-PKcs-deficient repair mechanism exhibited reduced V(D)J recombination efficiency, increased end resection, decreased polymerase-mediated insertions, loss of recombination fidelity and generated relatively higher rates of chromosome translocation as a consequence of dysregulated coding and signal end joining. Our study underscores DNA-PKcs in suppressing illegitimate chromosome rearrangement in both species.
2023-12-30 | GSE249453 | GEO