Figure 2  Reduced Testis Size and Germ Cell Apoptosis in Mice with Targeted Deletion in Dmrt7
(A) Testes from a 6-wk-old wild-type (+/+) mouse and a homozygous (−/−) Dmrt7 mutant littermate.
(B–D) Sections of testes from 14-d-old (B), 21-d-old (C), and 42-d-old mice (D) stained with hematoxylin and eosin. Wild-type is in left column and mutant in right. No significant difference is observed at 14 d (B), but by 21 d some tubules are lacking abundant spermatocytes (C, asterisk) or cells with typical apoptotic morphology are present (open arrowhead, C and D). Mutant tubules contain multinucleate cells (closed arrowhead, D).
(E and F) TUNEL labeling of Dmrt7-deficient mouse testes. Testes from wild-type and homozygous mutant littermates were analyzed by TUNEL labeling to detect apoptotic cells. Testis sections from 21-d-old (E) and 6-wk-old mice (F). Apoptotic cells (brown) are much more abundant in seminiferous tubules of homozygous Dmrt7 mutant mice relative to wild-type. Bars in (B–F) represent 100 μm.