Fig. 2. dpp is essential for repressing bam transcription in GSCs. Germaria in panels A-D are labeled for Hts (red, fusomes), GFP (green) and DAPI (blue), whereas the germaria in E-H are labeled for pMad (red), GFP (green), Hts (blue, fusomes) and DAPI (white; F,H). All the GSCs are indicated by asterisks, and cap cells in all the panels are marked by circles. (A) A germarial tip from a bam-GFP female cultured at 29°C for one week, showing no bam expression in GSCs. (B) A germarial tip from a bamGFP dpp^hr56/dpp^hr4 female cultured at 29°C for 2 days, showing that one of the two GSCs begins to express bam. (C,D) Germarial tips from bamGFP dpp^hr56/dpp^hr4 females cultured at 29°C for 4 (C) or 7 (D) days, showing that the only remaining GSC starts to express bam. (E,F) Germarial tip from a bam-GFP female cultured at 29°C for 4 days, showing high pMad accumulation and no bam expression in GSCs. (G,H) A germarial tip from a bamGFP dpp^hr56/dpp^hr4 female cultured at 29°C for 4 days, showing that two mutant GSCs have low pMad levels and begin to express bam. All micrographs are shown at the same scale. Scale bar: 10 µm.