Fig. 9

Daughter-strand gap repair. (a) A lesion in the DNA template (black triangle) blocks replication of the leading strand. Replication restart beyond the lesion produces a single-stranded daughter-strand gap (b) and (c) the RecFOR complex binds to the end of the gap and loads RecA protein onto the ssDNA. (d) The RecA-ssDNA filament invades the intact duplex arm of the replicating chromosome. (e) Branch migration and DNA synthesis (dashed line) produce Holliday junctions. (f) Resolution of the Holliday junctions restores the dsDNA structure. The DNA lesion is in dsDNA where it can be repaired by base excision or nucleotide excision repair (After Heller and Marians 2006)