Astrocytes Play a Key Role in Drosophila Mushroom Body Axon Pruning
Figure 3
The number of astrocytes at the MB remains constant throughout remodeling.
(A–E) Confocal Z-projections of alrm-GAL4 driven RedStinger expression (red, A–E) labeling astrocytes nuclei at 0 h APF (A), 6 h APF (B, E), 18 h APF (C) or 24 h APF (D). (A–D) Labeling astrocyte cell bodies shows that the number of the astrocytes does not significantly change during remodeling. (E) High magnification view of dorsal tip reveals that astrocytes (red) label only part of the repo+ nuclei in the vicinity of the MB lobe tip. (F) To characterize this quantitatively, we counted the number of astrocytes nuclei within 5 μM of the dorsal tip and found that only 1–2 astrocytes are located near the dorsal tip throughout remodeling. Magenta represents anti-FasII and anti-Repo staining. Red is alrm-GAL4 driven RedStinger. (G) Confocal Z-projections (G) or single slices (individual cells) of brains expressing alrm-Gal4 driven CD8-GFP in just a few cells (see materials and methods). While the 6 glial cells proximal to the dorsal tip are not labeled with mCD8::GFP (close-up of dorsal tip, region 5), four cells that are located further away from the lobe are (see close-ups of cell 1–4). Grey represents FasII and Repo staining (G1 and upper panels in close-ups), DAPI staining in the lower panels in close ups or alrm-Gal4 driven CD8-GFP (G2 and middle panels in close-ups). Magenta represents FasII and Repo staining and green represents alrm-Gal4 driven CD8-GFP in H3 and lower panels in close-ups. The scales bars are 20 μm. Genotypes: (A–E): w;UAS-RedStinger/+;alrm-GAL4/+. (G) y,w,hsFlp,FRT19A/y,w,hsFlp,19A,tubP-GAL80;alrm-GAL4;alrm-GAL4,UAS-mCD8::GFP.