Fig. 2. Diminished levels of Orbit/Mast lead to egg chambers with a reduced number of germline cells. (A) Western blot indicating the reduced levels of Orbit/Mast in total ovarian protein extracts of the indicated genotypes. (B) Western blot showing levels of Hts (Hu-li tai shao) ADD-95 and ADD-87 isoforms in ovarian total protein extracts. The ADD-95 isoform is present at similar levels in all four extracts, while the ADD-87 isoform is absent from orbit⁵/orbit⁵ and orbit⁶/orbit⁶ ovaries. Equal amount of samples were loaded on both Western blots and confirmed by staining with an anti-tubulin antibody. (C) Western blot indicating the age-dependent reduction of the expression level of Orbit/Mast in total ovarian protein extracts of the orbit⁶/orbit⁶ ovaries as normalised to wild type. (D) Wild-type (wt) and orbit⁶ (orbit) egg chambers were stained with anti-lamin (green) antibody and TOTO3 for DNA (blue). The orbit⁶ egg chambers contain fewer than 16 germline cells. They show no oocyte differentiation and all cells adopt nurse cell fate. Scale bar: 50 µm.