Double-strand DNA breaks articles from across Nature Portfolio

New work shows that in mammals, the iDDR motif of telomere factor TRF2 inhibits the MRE11–RAD50–NBS1 (MRN) complex at chromosome ends through a direct iDDR–RAD50 interaction. Unrelated protein motifs in yeasts inhibit MRN functions via an analogous mechanism, suggesting a convergent evolution in eukaryotes to control MRN action at telomeres.

Here, the authors show that PDHE1α accumulates at DNA double-strand breaks, in a PARylation-dependent manner, where it locally supplies acetyl-CoA for histone acetylation. These events facilitate remodeling of the chromatin landscape and efficient repair.

Deshpande et al show that MRN nuclease-dependent processing of DNA ends in human cells occurs at sites bound by DNA-PK. Chromatin immunoprecipitation analysis of DNA-PK, MRN, and CtIP supports a sequential model of pathway choice.

Here, the authors show that DYNLL1 accumulates at DNA double-strand breaks via 53BP1, where it inhibits MRE11-dependent end resection by disrupting its dimerization, and it restricts recruitment of the Shieldin complex.

In mitosis, genome integrity is maintained by DNA polymerase theta-dependent repair of DNA double-strand breaks, which is regulated by Polo-like kinase 1 activity.

Deregulation of transcription by oncogenes leads to collisions of RNA Polymerase II (RNAPII) with DNA replication machinery (transcription-replication conflicts, TRCs). This study shows that RNAPII activates ATM kinase at TRCs providing a mechanism for replication fork stalling and ATM activation at TRCs.

FAAP20 has roles in several homology-directed pathways of DNA double-strand break repair that are both independent and dependent on its binding partner FANCA and FANCA-mediated single strand annealing.

New work shows that in mammals, the iDDR motif of telomere factor TRF2 inhibits the MRE11–RAD50–NBS1 (MRN) complex at chromosome ends through a direct iDDR–RAD50 interaction. Unrelated protein motifs in yeasts inhibit MRN functions via an analogous mechanism, suggesting a convergent evolution in eukaryotes to control MRN action at telomeres.

Increasing evidence links RNA methyltransferases to DNA damage repair. METTL16 is now shown to antagonize homologous recombination by preventing DNA-end resection via MRE11. Thus, METTL16 may represent a cancer vulnerability that can be used to identify patients able to benefit from combination therapies with DNA-damaging agents.

The collapse of DNA replication forks leads to the formation of single-ended DNA double-strand breaks. One would have assumed that these breaks would be repaired as soon as possible. However, a recent study suggests that a delay in DNA polymerase θ-mediated end joining until mitosis, orchestrated by BRCA2 and RAD52, favors genomic stability.

Cells rely on two main pathways to repair DNA lesions, homologous recombination and non-homologous end-joining, and how they decide to use one machinery over the other is not clear. A recent study identifies ASTE1 as a regulator controlling pathway choice.

Nuclear DNA damage has detrimental effects on cellular homoeostasis and accelerates the ageing process. A new study causally links error-prone mitochondrial replication to increased nuclear DNA damage, thus suggesting that the hallmarks of ageing are associated with nuclear genome instability, a potential unifying denominator in the ageing process.