Pan-glial Myo induces phagocytic astrocyte transformation. (A–C) Astrocytes labeled with a membrane targeted GFP (UAS-mCD8::GFP) at wL3 (A), 4APF (B), and HE (C), showing the typical tranformation from circuit support cells with “wispy” processes at wL3 to phagocytic cells with vesicles (yellow arrows) at 4 h APF, to largely absent from the neuropil at HE. (D–F) Myo knocked down only in astrocytes with alrm-Gal4. Astrocytes look morphologically normal at wL3 (D), continue to transform into phagocytes by 4 h APF (E) with vesicles (yellow arrows), and then largely disappear from the neuropil by HE (F). (G–I) Visualization of astrocytes using a UAS-mCD8::Cherry when Myo is knocked down in all glia. Astrocytes look morphologically normal at wL3 (G) but fail to transform into phagocytes with vesicles at 4 h APF (H) and continue to persist, albeit without phagocytic vesicles, to HE (I). (J) EcR-B1 staining in a alrm-Gal4, UAS-LacZ (control) animal. (K and L) Expression of UAS-Myo^RNAi in all glia, EcR-B1 staining (magenta). Astrocyte membranes, green. (M and N) Expression of UAS-Myo^RNAi in astrocytes, EcR-B1 staining, magenta. Astrocyte membranes, green. Six to eight animals were checked for each time point and genotype shown in this figure, and the morphology and phenotypes shown are representative of what was observed. All scale bars are 20 µm.