Fig. 3. Moesin RNAi disorganizes F-actin and apical microvilli. (A, C) Confocal micrographs show F-actin staining (red) and Moesin immunolocalization (green). (A) In a 57% pd hs>IR-Moesin retina, photoreceptors lacking Moesin (arrowheads) are reduced in size and exhibit abnormal F-actin distribution. The asterisked ommatidium (enlarged, right) shows lack of Moesin in R1, R3 and R7. (B) An electron micrograph of 57% pd hs>IR-Moesin ommatidium shows loosely organized rhabdomere microvilli (compare with Fig. 5A); the rhabdomere of R5 is reduced. (C) GMR>IR-Moesin photoreceptor apical membrane organization is devastated by Moesin loss. A single photoreceptor (arrowhead) retains strong Moesin signal and an intact rhabdomere. (D) Electron micrograph of 70% pd GMR>IR-Moesin ommatidium shows severe rhabdomere defects. The asterisked photoreceptor lacks a rhabdomere. Adherens junctions appear normal (B,D; arrows). Scale bars: 10 µm in A,C; 1 µm in B,D.