FIG. 4.

(A) Morphology of spermatogenesis appears normal in the testis of wild-type and UBC4-testis homozygous mice at day 40 of life. Shown are representative sections of the testis stained with hematoxylin-eosin at stages VII and XII. (B) Rates of apoptosis in the testis are similar in wild-type and UBC4-testis homozygous mice at days 35 and 40. Testis sections were subjected to TUNEL staining, and the numbers of apoptotic cells per tubule were determined (n = 5 for each group at day 40, n = 9 for each group at day 35.). KO, homozygous; WT, wild type.