fig3

Figure 3. Repair and mis-repair of one-ended DSBs at collapsed replication forks. Single-strand breaks (SSB) and single-strand DNA lesions may be repaired prior to replication. If encountered by a replication fork, SSBs and single-strand lesions cause fork collapse and fork stalling, respectively. Stalled forks may collapse when cleaved by MUS81 or EEPD1. Collapsed forks create one-ended DSBs that can initiate fork restart by HR, or they may be joined to other DSB ends (at collapsed forks or frank DSBs) by NHEJ or alt-NHEJ, creating large-scale genome rearrangements. DSBs: DNA double-strand breaks; HR: homologous recombination; NHEJ: non-homologous end-joining