Fig. 6. Ring canal organisation is affected in egg chambers of orbit⁶ mutants. (A-D) Germaria were stained with rhodamine-phalloidine (red), anti-Filamin (green) antibody and TOTO3 to reveal DNA (blue). (A) Wild-type egg chamber in which Filamin and F-actin co-localise in the ring canals. Scale bar: 50 µm. (B) Egg chamber of 1-day old orbit⁶ female containing seven nurse cell nuclei and six ring canals. Filamin and F-actin accumulate not only in the rims but also in the lumen of the ring canals. Note the weak F-actin staining in the cortex of the nurse cells. Scale bar: 10 µm. (C) Filamin and F-actin are not restricted to the rims of ring canals in orbit⁶ egg chambers. Scale bar: 5 µm. (D) Severely affected egg chambers from 3-day old orbit⁶ female with a single large nurse cell nucleus; ring canals fail to form although filamentous structures containing Filamin and F-actin are visible. Scale bar: 10 µm. (E-G) Germaria were stained with anti-Orbit (red), anti-HtsRC (green) antibodies and TOTO3 to reveal DNA (blue). (E) Wild-type egg chamber showing the HtsRC and Orbit/Mast (inset) proteins in the ring canals. Scale bar: 25 µm. (F) Egg chamber from 1-day old orbit⁶ female in which HtsRC accumulates in the rims and obstructs the lumen of the ring canals. Orbit/Mast staining is weak in the cortex of the nurse cells. Scale bar: 10 µm. (G) Abnormal egg chamber of 3-day old orbit⁶ female showing irregular structures containing HtsRC protein, some of which resemble ring canals that have completely occluded lumens. Scale bar: 10 µm.