Fig. 4. Function of Ad4BP/SF-1 in the gonadal cortex before sexual differentiation. (A-E) Chick embryonic fibroblasts producing Ad4BP/SF-1 (A,B,D) and AP (C,E)-encoding viruses were implanted into the right presumptive gonad of both sexes at stage 11-12. The distribution of Ad4BP/SF-1-encoding viruses was examined by in situ hybridization for chick Ad4BP/SF-1 (A). As chick Ad4BP/SF-1 was used for the implantation study, in situ hybridization detected both endogenous and exogenous expression. The arrowhead in A indicates viral distribution in the developing right gonadal cortex, where Ad4BP/SF-1 gene is not endogenously activated (see Fig. 1K). The effects on cell proliferation (B,C) and cortical thickness (D,E) were examined as described in Fig. 3. (F,G) Relative numbers of BrdU-positive cells in the cortex (F) and medulla (G). Scale bars: 100 µm in A-C; 50 µm in D,E.