FIGURE 10.

The effect of the gelsolin homology domains of Fli-I on actin organization in Drosophila egg chambers. (A,A’) Actin organization in nurse cells of a wild type Drosophila egg chamber in stage 10B is characterized by the presence of cortical actin (yellow arrows), ring canals (red arrowheads) and cytoplasmic actin cables growing from the plasma membrane to the nucleus. Actin is shown in (A) in grayscale, an overlay of DAPI (in cyan) and actin (in red) are shown in (A’). (B,B’) Maternal expression of a UAS-lacZ control does not affect actin organization in the nurse cells. (C–D’) Maternal expression of UAS-Fli-I GH16 (C,C’) or UAS-Fli-I GH13 (D,D’) severely impairs cytokinesis in the nurse cells resulting in fused cells with reduced cortical actin level, ring canals are not evident and the nuclear positioning cytoplasmic actin cables are also missing. (E,E’) By contrast, in UAS-Fli-I GH46 expressing egg chambers actin organization is not altered as compared to wild type. Anterior edge of the oocyte is visible on the right side of each panel; anterior is on the left, posterior is on the right. Scale bar = 50 μm.