Fig. 5. Pvr acts in hemocytes and not midline glia for proper CNS patterning. (A,B) Stage 16 embryos stained with anti-wrapper antibody to visualize midline glia. Pvr⁵³⁶³ midline glia (B) are indistinguishable from wild type (A). (C,D) Stage 16 (C) Sim-Gal4;UAS-Pvr^DN and (D) Gcm-Gal4;UAS-Pvr^DN embryos stained with mAb BP102 to visualize CNS axons. Sim-Gal4;UAS-Pvr^DN embryos are indistinguishable from wild type, with commissures and longitudinal tracts forming a rectangular axon scaffold in each segment (arrow). Gcm-Gal4;UAS-Pvr^DN embryos resemble Pvr embryos, with the axon scaffold having a rounded appearance in each segment (arrow). (E,F) Stage 16 (E) Sim-Gal4;UAS-Pvr^DN and (F) Gcm-Gal4;UAS-Pvr^DN embryos stained with anti-Repo antibody to visualize glia. Sim-Gal4;UAS-Pvr^DN embryos have glia in normal positions, with only few glia located between commissures in each segment (arrowhead), while many segments of Gcm-Gal4;UAS-Pvr^DN embryos have clusters of glia near the midline (arrowheads). (G-I) Stage 16 (G) wild type (Canton-S), (H) Pvr^KO2 and (I) Gcm-Gal4;UAS-Pvr^DN embryos stained with anti-Croquemort to visualize hemocytes. In wild type, hemocytes are dispersed throughout the embryo, while in Pvr mutants and Gcm-Gal4;UAS-Pvr^DN embryos hemocytes are largely clustered near the dorsal and anterior regions of the embryo. Anterior is towards the left and dorsal is towards the top.