Figure 3

Magea genes protected germ cells from apoptosis after genotoxic stress induced by ENU.

(A) Testicular sections of 3-month-old wild-type and Magea^−/Y mice 1 week after ENU treatment (late response assay). Scale bar, 100 μm. Further enlarged images of the areas in dashed boxes are shown in the right panels. Red arrows indicate apoptotic cells. Scale bar, 50 μm. (B,C) Increased numbers of apoptotic cells were observed in Magea^−/Y mice by TUNEL staining. Apoptotic cells were counted in 9 whole sections for each genotype. Scale bar, 50 μm. (D) Immunofluorescence of activated caspase-3 and SCP3 in testicular sections of Magea^−/Y mice. Scale bar, 50 μm. (E) Quantification of cells with positive activated caspase-3 staining in each seminiferous tubule (n = 223 for wild-type and n = 202 for Magea^−/Y, p < 0.001). (F,G) Representative flow cytometry dot plot of Annexin V–FITC and PI staining for the detection of testicular apoptosis (n = 6). Magea^−/Y mice showed significantly increased apoptosis after exposure to ENU for 1 week. ***p < 0.001.