Fig. 3. Analysis of gonad differentiation using immunofluorescent histochemistry and confocal microscopy. (A-C) E12.5 Gata4^ki/ki gonads at the time when testis cords are beginning to develop in normal XY gonads. (D-F) E13.5 XY Fog2^–/– gonads at the time when testis cord are normally well developed and surrounded by a basal lamina in control XY gonads. (A,D) XX control gonads, (B,E) XY control gonads and (C,F) mutant XY gonads. Laminin, green; GATA4, red; PECAM, blue. In each image the gonad is above the mesonephros.