Fig. 3.

Reduced spermatogonia proliferation during postnatal testis development. (A-L) Paraffin testis sections from postnatal day (P)0 (A-D), P5 (E-H) and 2-week-old (2w; I-L) wild-type (WT; +/+) and mutant (−/−) RanBPM mice stained with Hematoxylin and Eosin (H&E) for histology (A,B,E,F,I,J), the proliferation marker proliferating cell nuclear antigen (PCNA) (C,D,K,L) or TUNEL for apoptosis (G,H). At P0, the mutant testis appears normal as, like in WT, Sertoli cells are proliferating (D) and gonocytes (arrows in D) are present. At 2 weeks, mutant tubules are smaller and spermatogonia and spermatocytes are less abundant than in WT. Scale bars: 100 μm. (M,N) BrdU labeling showing scattered proliferating germ cells (red) in a mutant testis at P8, compared with the even labeling in P8 WT tubules. (O) Quantification of BrdU-labeled spermatogonia at P8. Scale bars: 200 μm. Data were obtained from cell number quantification of ten separate fields from each genotype. *P<0.001, Student's t-test.