Ontology highlight
ABSTRACT:
PROVIDER: PRJNA814398 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR18286300_1.fastq.gz | Fastqsanger.gz | |||
| SRR18286300_2.fastq.gz | Fastqsanger.gz | |||
| SRR18286301_1.fastq.gz | Fastqsanger.gz | |||
| SRR18286301_2.fastq.gz | Fastqsanger.gz | |||
| SRR18286302_1.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 82 |
Similar Datasets
Project description:53BP1 governs a specialized, context-specific branch of the classical non-homologous end joining DNA double-strand break repair pathway. Mice lacking 53bp1 (also known as Trp53bp1) are immunodeficient owing to a complete loss of immunoglobulin class-switch recombination, and reduced fidelity of long-range V(D)J recombination. The 53BP1-dependent pathway is also responsible for pathological joining events at dysfunctional telomeres, and its unrestricted activity in Brca1-deficient cellular and tumour models causes genomic instability and oncogenesis. Cells that lack core non-homologous end joining proteins are profoundly radiosensitive, unlike 53BP1-deficient cells, which suggests that 53BP1 and its co-factors act on specific DNA substrates. Here we show that 53BP1 cooperates with its downstream effector protein REV7 to promote non-homologous end joining during class-switch recombination, but REV7 is not required for 53BP1-dependent V(D)J recombination. We identify shieldin—a four-subunit putative single-stranded DNA-binding complex comprising REV7, c20orf196 (SHLD1), FAM35A (SHLD2) and FLJ26957 (SHLD3)— as the factor that explains this specificity. Shieldin is essential for REV7-dependent DNA end-protection and non-homologous end joining during class-switch recombination, and supports toxic non-homologous end joining in Brca1-deficient cells, yet is dispensable for REV7-dependent interstrand cross-link repair. The 53BP1 pathway therefore comprises distinct double-strand break repair activities within chromatin and single-stranded DNA compartments, which explains both the immunological differences between 53bp1- and Rev7- deficient mice and the context specificity of the pathway.
2018-07-26 | PXD009650 | Pride
Project description:Ubiquitination is a crucial post-translational modification required for the proper repair of DNA double-strand breaks (DSBs) induced by ionising radiation (IR). DSBs are mainly repaired through homologous recombination (HR) when template DNA is present and non-homologous end joining (NHEJ) in its absence. Additionally, microhomology-mediated end joining (MMEJ) and single strand annealing (SSA) provide back-up DSBs repair pathways. However, the mechanisms controlling their use remain poorly understood. By employing a high-resolution CRISPR screen of the ubiquitin system after IR, we systematically uncover genes required for cell survival and elucidate a critical role of the E3 ubiquitin ligase SCFcyclin F in cell cycle dependent DSB repair. We show that SCFcyclin F -mediated EXO1 degradation prevents DNA end resection in mitosis, allowing MMEJ to take place. Moreover, we identify a conserved cyclin F recognition motif, distinct from the one used by other cyclins, with broad implications in cyclin specificity for cell cycle control.
2024-10-17 | PXD051841 | Pride
Project description:RIF1 acts downstream of 53BP1 to coordinate DNA double strand break repair pathway choice between non-homologous end joining (NHEJ) and homologous recombination (HR). Here we identified ASF1 as an endogenous RIF1-associated protein. We showed that ASF1 forms complex with RIF1 and regulates RIF1-dependent functions in DNA damage response.
2022-06-09 | PXD027727 | Pride
Project description:Determining the balance between DNA double strand break repair (DSBR) pathways is essential for understanding treatment response in cancer. We report a novel method for simultaneously measuring non-homologous end joining (NHEJ), homologous recombination (HR), and microhomology-mediated end joining (MMEJ). This approach revealed enhanced MMEJ and HR in glioblastoma (GBM) xenograft models with acquired temozolomide (TMZ) resistance. Knockdown of proteins in either pathway enhanced killing by TMZ, and a targeted screen identified pharmacological-grade dual HR/MMEJ inhibitors, including AZD1390, an ATM kinase inhibitor. AZD1390 suppressed DSB end resection, blocked phosphorylation of end protection proteins in response to DNA damage, and potentiated TMZ in treatment-naïve and treatment-resistant models. TP53-mutant GBMs were most susceptible to AZD1390 in combination with DNA-damaging agents due to elevated ATM-dependent HR/MMEJ, preferential activation of these pathways in response to DNA damage, and a defective G2/M checkpoint, which caused these GBMs to enter mitosis despite unrepaired DNA damage, leading to cell death via apoptosis. This report establishes ATM-dependent HR and MMEJ as targetable resistance mechanisms in TP53-mutant GBM and establishes an approach for simultaneously measuring multiple DSBR pathways in treatment selection and oncology research.
2024-03-08 | PXD047837 | Pride
Project description:Mechanisms of DNA double strand break repair in Arabidopsis non-homologous end joining mutants
| PRJNA100645 | ENA
Project description:Cell cycle is a major determinant of DNA double-strand break (DSB) repair pathway choice with homologous recombination (HR) that is most active in S phase cells and non-homologous end-joining (NHEJ) that dominates in G1 phase cells. A third less well-defined mechanism, 'alternative end-joining', has been shown to promote error-prone repair in NHEJ- or HR-deficient cells. Here, we have used a physiologic system of NHEJ-mediated genomic rearrangements induced by the site-specific RAG1/2 endonuclease in G1 cells to investigate the fate of unrepaired G1 DSBs upon entry into the cell cycle. We show that, in the absence of XRCC4, alternative end-joining rescues RAG-induced DSB repair and promotes chromosome translocations upon G1 cell cycle exit.
2020-08-24 | GSE138136 | GEO
Project description:Cell cycle is a major determinant of DNA double-strand break (DSB) repair pathway choice with homologous recombination (HR) that is most active in S phase cells and non-homologous end-joining (NHEJ) that dominates in G1 phase cells. A third less well-defined mechanism, 'alternative end-joining', has been shown to promote error-prone repair in NHEJ- or HR-deficient cells. Here, we have used a physiologic system of NHEJ-mediated genomic rearrangements induced by the site-specific RAG1/2 endonuclease in G1 cells to investigate the fate of unrepaired G1 DSBs upon entry into the cell cycle. We show that, in the absence of XRCC4, alternative end-joining rescues RAG-induced DSB repair and promotes chromosome translocations upon G1 cell cycle exit.
2020-08-24 | GSE138135 | GEO
Project description:The RNA-guided DNA endonuclease Cas9 is a powerful tool for genome editing. Little is known about the kinetics and fidelity of the double-strand break (DSB) repair process that follows a Cas9 cutting event in living cells. Here, we developed a strategy to measure the kinetics of DSB repair for single loci in human cells. Quantitative modeling of repaired DNA in time series after Cas9 activation reveals variable and often slow repair rates, with half-life times up to ~10 h. Furthermore, repair of the DSBs tends to be error-prone. Both classical and microhomology-mediated end-joining pathways contribute to the erroneous repair. Estimation of their individual rate constants indicates that the balance between these two pathways changes over time and can be altered by additional ionizing radiation. Our approach provides quantitative insights into DSB repair kinetics and fidelity in single loci, and indicates that Cas9-induced DSBs are repaired in an unusual manner.
2018-05-01 | GSE113129 | GEO
Project description:Oncogene amplification on extrachromosomal DNA (ecDNA) is a pervasive driver event in cancer, yet our understanding of how ecDNA forms is limited. Here, we couple a CRISPR-based method for ecDNA induction with extensive characterization of newly formed ecDNA to examine their biogenesis. We find that DNA circularization is efficient, irrespective of 3D genome context, with formation of 800kb, 1 Mb, and 1.8 Mb ecDNAs reaching or exceeding 15%. We show non-homologous end joining and microhomology-mediated end joining both contribute to ecDNA formation, while inhibition of DNA-PKcs and ATM have opposing impacts on ecDNA formation. EcDNA and the corresponding chromosomal excision scar can form at significantly different rates and respond differently to DNA-PKcs and ATM inhibition. Taken together, our results support a model of ecDNA formation in which double strand break ends dissociate from their legitimate ligation partners prior to joining of illegitimate ends to form the ecDNA and excision scar.
2024-07-25 | GSE273081 | GEO