Nonhomologous end-joining uses distinct mechanisms to repair each strand of a double strand break.

ABSTRACT: Nonhomologous end-joining repairs chromosomal double strand breaks, but it is unknown whether both strands are repaired by this pathway, and if one strand break's repair path impacts the other. Here, we show that nonhomologous end-joining employs both of two a priori possible strategies. Strand breaks that can be directly ligated are joined near-simultaneously, with no effect of one strand break's repair path on the other. More complex end structures require obligatorily ordered repair. The first strand to be repaired is used as template for repair of the opposite/second strand break, with the latter repair reaction occurring fastest when also coupled to nonhomologous end-joining. Enforced asymmetry in repair of each strand break can extend to the gap-filling polymerase employed, and wheth

SUBMITTER: Luthman AJ 

PROVIDER: S-EPMC12748747 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature