Fig. 3. GP130-deficient embryos have almost normal numbers of PGCs. PGCs express the gfp marker (green), and GP130 staining (red) was performed using the gGP130 antibody. Staining and counts were performed on gonads dissected at E13.5. (A-D) GP130 expression in a / ovary (A), a wild-type ovary (B), a / testis (C), and a wild-type testis (D). Both male and female / gonads exhibit reduced staining. (E) Germ cell counts in /, /+ and +/+ littermates. PGCs were counted in individual testes or ovaries as described (Materials and Methods). The males exhibit a slight reduction in PGC numbers, which is statistically significant in the case of the / (-/-) littermates (Student's t-test, P<0.02). Error bars show standard deviations. Scale bars: 20 µm.