Fig. 7

Uncompleted DNA double-strand breaks repair and synapsis in Cdkn2aip^−/− spermatocytes. A Immunostaining of SYCP1(green) and SYCP3(red) on chromosome spreads of spermatocytes from P35 Cdkn2aip^+/+ and Cdkn2aip^−/− testes, n = 3 mice for each group. Scale bars, 10 μm. B Frequency of meiotic prophase I stages. n = 3 mice for each group, and 50 spermatocytes from each mouse were examined. Data are presented as mean ± SD, *P < 0.05 **P < 0.01 by two-tailed Student’s-test. C Immunostaining of γH2AX (green) and SYCP3(red) on chromosome spreads of spermatocytes from P35 Cdkn2aip^+/+ and Cdkn2aip^−/− testes, n = 3 mice for each group. Scale bars, 10 μm. D Statistical results of (C). Data are presented as average percentage, n = 3 mice for each group, and 50 pachytene spermatocytes were counted for each mouse. E Immunostaining of RAD51 (green) and SYCP3(red) on chromosome spreads of spermatocytes from P35 Cdkn2aip^+/+ and Cdkn2aip^−/− testes, n = 3 mice for each group. Scale bars, 10 μm. F Immunostaining of MLH1 (green) and SYCP3(red) on chromosome spreads of spermatocytes from P35 Cdkn2aip^+/+ and Cdkn2aip^−/− testes, n = 3 mice for each group. Scale bars, 10 μm. G TUNEL assays on Cdkn2aip^+/+ and Cdkn2aip.^−/− testes. Arrows point to apoptotic cells stained in green. Scale bar, 50 μm. H Statistical results of (E–G). 50 spermatocytes of pachytene stage were counted for RAD51 and MLH1 foci. 10 seminiferous tubules were counted in each group. Data are presented as mean ± S.D. Student’s t test; **P < 0.01 ***P < 0.001