ATM and 53BP1 regulate alternative end joining-mediated V(D)J recombination
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1032082 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR26521412_1.fastq.gz | Fastqsanger.gz | |||
| SRR26521412_2.fastq.gz | Fastqsanger.gz | |||
| SRR26521413_1.fastq.gz | Fastqsanger.gz | |||
| SRR26521413_2.fastq.gz | Fastqsanger.gz | |||
| SRR26521414_1.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 84 |
Similar Datasets
Project description:The critical role of the alternative end joining (AEJ) repair mechanism in V(D)J recombination for B and T lymphocyte development, particularly in the absence of the key non-homologous end joining (NHEJ) component Ku70, is not well understood. AEJ involves functionally redundant factors such as Parp1 vs Polθ and Lig3 vs Lig1, making it unclear which factors are responsible for repairing V(D)J recombination. Additionally, the regulatory mechanism of AEJ remains enigmatic. In this study, we utilized the murine Igκ antigen locus as a model and employed gene editing and HTGTS-Seq pipelines to systematically evaluate potential factors involved in V(D)J recombination. We assessed various aspects of recombination, including efficiency, V gene usage, end resection, joining fidelity, repair patterns, and inter-chromosome translocation. Our findings highlight the Parp1-XRCC1-Lig3 axis as a key mediator of V(D)J recombination, regulated by 53BP1 and ATM. This study advances our understanding of AEJ in DNA damage repair and contributes to our knowledge of lymphocyte development in immunology.
2023-12-31 | GSE246239 | GEO
Project description:The critical role of the alternative end joining (AEJ) repair mechanism in V(D)J recombination for B and T lymphocyte development, particularly in the absence of the key non-homologous end joining (NHEJ) component Ku70, is not well understood. AEJ involves functionally redundant factors such as Parp1 vs Polθ and Lig3 vs Lig1, making it unclear which factors are responsible for repairing V(D)J recombination. Additionally, the regulatory mechanism of AEJ remains enigmatic. In this study, we utilized the murine Igκ antigen locus as a model and employed gene editing and HTGTS-Seq pipelines to systematically evaluate potential factors involved in V(D)J recombination. We assessed various aspects of recombination, including efficiency, V gene usage, end resection, joining fidelity, repair patterns, and inter-chromosome translocation. Our findings highlight the Parp1-XRCC1-Lig3 axis as a key mediator of V(D)J recombination, regulated by 53BP1 and ATM. This study advances our understanding of AEJ in DNA damage repair and contributes to our knowledge of lymphocyte development in immunology.
2023-12-31 | GSE242952 | GEO
Project description:53BP1 regulates DNA end-joining in lymphocytes, diversifying immune antigen receptors. This involves nucleosome-bound 53BP1 at DNA double-stranded breaks (DSBs) recruiting RIF1 and shieldin, a poorly understood DNA-binding complex. The 53BP1-RIF1-shieldin axis is pathological in BRCA1-mutated cancers, blocking homologous recombination (HR) and driving illegitimate non-homologous end-joining (NHEJ). However, how this axis regulates DNA end-joining and HR suppression remains unresolved. We investigated shieldin and its interplay with CST, a complex recently implicated in 53BP1-dependent activities. Immunophenotypically, mice lacking shieldin or CST are equivalent, with class-switch recombination co-reliant on both complexes. DNA damage-responsive signalling promotes shieldin-CST interaction, demonstrating shieldin as a DSB-specific CST adaptor. Furthermore, DNA polymerase ζ functions downstream of shieldin, establishing DNA fill-in synthesis as the physiological function of shieldin-CST. Lastly, 53BP1 suppresses HR and promotes NHEJ in BRCA1-deficient cells independently of shieldin. These findings showcase the resilience of the 53BP1 pathway, achieved through the collaboration of chromatin-bound 53BP1 complexes and DNA end-processing effector proteins.
2024-08-27 | PXD045534 | Pride
Project description:RAG endonuclease initiates V(D)J recombination by cleaving recombination signal sequences (RSSs), subsequently repaired by classical nonhomologous end-joining (c-NHEJ). However, 53BP1, as a key DNA damage response (DDR) factor promoting c-NHEJ, is dispensable for V(D)J recombination. Here, we report that 53BP1 orchestrates sequence strength of RAG targets to shape end-joining features during V(D)J recombination. Deficiency of 53BP1, rather than other DDR factors, specifically increases junctional microhomology (MH) of cryptic RSS (cRSS) recombination instead of RSS recombination. Depletion of RIF1 or Shieldin, downstream factors of 53BP1, partially mimics the phenotypes of 53BP1-deficiency. Notably, loss of RNF168, rather than other classical resection and alternative end-joining factors, is sufficient to fully rescue 53BP1-deficiency-mediated increase of junctional MH during cRSS recombination. Remarkably, RAG mutant and RSS score analyses indicate that sequence strength of RAG targets determines the unique roles of 53BP1 in balancing end-joining outcomes. Our findings provide deeper mechanistic insights into DNA damage repair for RAG cleaved on- and off-targets during V(D)J recombination.
2026-04-09 | GSE270090 | GEO
Project description:RAG endonuclease initiates V(D)J recombination by cleaving recombination signal sequences (RSSs), subsequently repaired by classical nonhomologous end-joining (c-NHEJ). However, 53BP1, as a key DNA damage response (DDR) factor promoting c-NHEJ, is dispensable for V(D)J recombination. Here, we report that 53BP1 orchestrates sequence strength of RAG targets to shape end-joining features during V(D)J recombination. Deficiency of 53BP1, rather than other DDR factors, specifically increases junctional microhomology (MH) of cryptic RSS (cRSS) recombination instead of RSS recombination. Depletion of RIF1 or Shieldin, downstream factors of 53BP1, partially mimics the phenotypes of 53BP1-deficiency. Notably, loss of RNF168, rather than other classical resection and alternative end-joining factors, is sufficient to fully rescue 53BP1-deficiency-mediated increase of junctional MH during cRSS recombination. Remarkably, RAG mutant and RSS score analyses indicate that sequence strength of RAG targets determines the unique roles of 53BP1 in balancing end-joining outcomes. Our findings provide deeper mechanistic insights into DNA damage repair for RAG cleaved on- and off-targets during V(D)J recombination.
2026-04-09 | GSE270088 | GEO
Project description:RAG endonuclease initiates V(D)J recombination by cleaving recombination signal sequences (RSSs), subsequently repaired by classical nonhomologous end-joining (c-NHEJ). However, 53BP1, as a key DNA damage response (DDR) factor promoting c-NHEJ, is dispensable for V(D)J recombination. Here, we report that 53BP1 orchestrates sequence strength of RAG targets to shape end-joining features during V(D)J recombination. Deficiency of 53BP1, rather than other DDR factors, specifically increases junctional microhomology (MH) of cryptic RSS (cRSS) recombination instead of RSS recombination. Depletion of RIF1 or Shieldin, downstream factors of 53BP1, partially mimics the phenotypes of 53BP1-deficiency. Notably, loss of RNF168, rather than other classical resection and alternative end-joining factors, is sufficient to fully rescue 53BP1-deficiency-mediated increase of junctional MH during cRSS recombination. Remarkably, RAG mutant and RSS score analyses indicate that sequence strength of RAG targets determines the unique roles of 53BP1 in balancing end-joining outcomes. Our findings provide deeper mechanistic insights into DNA damage repair for RAG cleaved on- and off-targets during V(D)J recombination.
2026-04-09 | GSE270086 | GEO
Project description:RAG endonuclease initiates V(D)J recombination by cleaving recombination signal sequences (RSSs), subsequently repaired by classical nonhomologous end-joining (c-NHEJ). However, 53BP1, as a key DNA damage response (DDR) factor promoting c-NHEJ, is dispensable for V(D)J recombination. Here, we report that 53BP1 orchestrates sequence strength of RAG targets to shape end-joining features during V(D)J recombination. Deficiency of 53BP1, rather than other DDR factors, specifically increases junctional microhomology (MH) of cryptic RSS (cRSS) recombination instead of RSS recombination. Depletion of RIF1 or Shieldin, downstream factors of 53BP1, partially mimics the phenotypes of 53BP1-deficiency. Notably, loss of RNF168, rather than other classical resection and alternative end-joining factors, is sufficient to fully rescue 53BP1-deficiency-mediated increase of junctional MH during cRSS recombination. Remarkably, RAG mutant and RSS score analyses indicate that sequence strength of RAG targets determines the unique roles of 53BP1 in balancing end-joining outcomes. Our findings provide deeper mechanistic insights into DNA damage repair for RAG cleaved on- and off-targets during V(D)J recombination.
2026-04-09 | GSE270092 | GEO
Project description:IgH class switch recombination (CSR) in B lymphocytes switches IgH constant regions to change antibody functions. CSR is initiated by DNA double strand breaks (DSBs) within a donor IgH switch (S) region and a downstream acceptor S region. CSR is completed by fusing donor and acceptor S region DSB ends by classical non-homologous end-joining (C-NHEJ) and, in its absence, by alternative end-joining (A-EJ) that is more biased to use longer junctional micro-homologies (MHs). Deficiency for DSB response (DSBR) factors, including ATM and 53BP1, variably impair CSR end-joining, with 53BP1 deficiency having the greatest impact. However, studies of potential impact of DSBR factor deficiencies on MH-mediated CSR end-joining have been technically limited. We now use a robust DSB joining assay to elucidate impacts of deficiencies for DSBR factors on CSR and chromosomal translocation junctions in primary mouse B cells and CH12F3 B lymphoma cells. Compared to wild-type, CSR and c-Myc to S region translocation junctions in the absence of 53BP1, and to a lesser extent other DSBR factors, have increased MH-utilization; indeed, 53BP1-deficient MH-profiles resemble those associated with C-NHEJ deficiency. Yet, translocation junctions between c-Myc DSB and general DSBs genome-wide are not MH-biased in ATM-deficient versus wild-type CH12F3 cells and less biased in 53BP1- and C-NHEJ-deficient cells than CSR junctions or c-Myc to S region translocation junctions. We discuss potential roles of DSBR factors in suppressing increased MH-mediated DSB end-joining and features of S regions that may render their DSBs prone to MH-biased end-joining in the absence of DSBR factors.
2018-01-08 | GSE106922 | GEO
Project description:The shieldin (SHLD) complex, composed of SHLD1, SHLD2, SHLD3 and MAD2L2/REV7, acts downstream of 53BP1 to counteract DNA double-strand break (DSB) end-resection and promote non-homologous end-joining (NHEJ). While 53BP1 is essential for immunoglobulin heavy chain class switch recombination (CSR), long-range V(D)J recombination and for repair of RAG-induced DSBs in XLF-deficient cells, the role of SHLD in these activities remains elusive. Here, we report that contrary to 53BP1, SHLD1 is dispensable for lymphocyte development and V(D)J recombination, even in the sensitized XLF-deficient background or for the joining of distant V(D)J segments. By contrast, SHLD1 restricts resection at AID-induced DSB ends in both NHEJ-proficient and NHEJ-deficient B cells, providing an end-protection mechanism that permits productive CSR. Finally, we show that this end-protection function is required for orientation-specific joining of AID-initiated DSBs. We propose that 53BP1 promotes V(D)J recombination and CSR through two distinct mechanisms; the synapsis of V(D)J segments and switch regions within chromatin independently of SHLD and the protection of AID-DSB ends against resection mediated by SHLD.
2022-05-11 | GSE202567 | GEO
Project description:RAG endonuclease initiates immunoglobulin heavy chain (Igh) V(D)J recombination by cleaving V, D and J gene segments flanked by recombination signal sequences (RSSs), subsequently joined exclusively by classical nonhomologous end joining (c-NHEJ). While 53BP1, a key DNA damage response (DDR) factor promoting c-NHEJ, was reported to be dispensable for Igh V(D)J recombination. Here, we report that 53BP1 is a unique DDR factor playing unrecognized roles in joining RAG-initiated DNA breaks. Both RAG-cleaved RSSs and cryptic RSSs (cRSSs) are joined by c-NHEJ. Deficiency of 53BP1, rather than other DDR factors, slightly decreased the proximal V(D)J recombination without affecting c-NHEJ of RAG-initiated RSS breaks, but significantly increased microhomology (MH)-mediated alternative end joining (A-EJ) of RAG-initiated cRSS breaks, indicating that 53BP1 is specifically required for c-NHEJ of RAG-initiated cRSS breaks. Thus, our findings provide new insights into the distinct roles of 53BP1 in joining RAG-cleaved on- and off-targets during exclusively c-NHEJ-mediated V(D)J recombination
2026-04-09 | GSE270087 | GEO