Fig. 8.

RAD18 functions in the repair of a subset of persistent DSBs in meiotic prophase. (A-C) Double immunostaining of Sycp1 KO spermatocyte nuclei with anti-SYCP3 (red) and (A) anti-γH2AX (green), (B) anti-RAD51 (green) and (C) anti-RAD18 (green) antibodies. X and Y chromosomes are indicated as X and Y, respectively. The X and Y chromosomes are shown in the white circles. (D) Triple immunostaining of wild type (only the merge is shown) and Rad54 KO (separate images are shown) in late-pachytene nuclei with anti-SYCP3 (red), anti-RAD18 (green) and anti-γH2AX (blue) antibodies. (E) The percentage of nuclei containing persistent RAD18 patches in late pachytene is shown. 100 nuclei were examined in a control and a Rad54 KO mouse. **P<0.01 (Chi-squared test). (F) Double immunostaining of control (ctr) and Rad18 KD spermatocyte nuclei with anti-SYCP3 (red) and anti-γH2AX (green). Arrows indicate γH2AX, demonstrating persistent DSBs at autosomal regions. (G) Graph showing the percentage of persistent γH2AX foci in late diplotene of 4-week-old and 19-week-old control and Rad18 KD mice, and in wild-type and Hr6b KO mice. Blue bars indicate control or wild type, and red bars indicate Rad18 KD or Hr6b KO. **P<0.01 (Chi-squared test).