Figure 5.

Timing and expression levels of the male marker Sox9 is rescued in the B6/Line11-13-Y^POS across critical stages of early gonadogenesis, but female marker FoxL2 is not fully extinguished. Using fluorescence immunohistochemistry, we stained embryonic gonads from B6-Y^B6, B6-Y^POS, LineB6/11-13-Y^POS, and B6-XX animals during sex determination (E11.5–E12.5). B6-Y^POS gonads showed diminished expression of Sox9 protein (green) compared to B6-Y^B6 at all time points assayed and had significant expression of FoxL2 (red). Both timing and qualitative expression levels of Sox9 were rescued in the heterozygous LineB6/11-13-Y^POS embryonic gonads. FoxL2 expression in LineB6/11-13-Y^POS gonads was strongly diminished to much lower levels than in the B6-Y^POS gonads.