Fig. 8.

IHC confirmed the findings obtained by microarray analysis and qRT-PCR for Stra8 (GCs). The occurrence of STRA8 protein revealed obvious differences between WT (A,C) and SCCx43KO (B,D) mice. In seminiferous cords of the 8-day-old WT mice, many spermatogonia and first preleptotene spermatocytes show an intensive staining for STRA8 (A). By contrast, only single cells of the SCCx43KO mice revealed an immunoreactivity for STRA8 (B). Note the immunonegative spermatogonia in B (arrows). In adult WT mice, a stage-specific immunoreaction for STRA8 can be seen (C), whereas no immunoreaction at all can be detected in seminiferous tubules of adult mutants showing an arrest of spermatogenesis at the level of spermatogonia (arrow, D). Insert in A: representative negative control for STRA8 experiments. Scale bars: (A,B) 50 μm; (C,D) 100 μm.