Representative images of Drosophila 3rd instar larvae expressing the indicated transgenes in glial cells. repo-GAL4 was used to drive the expression of UAS-dRasG12V in glia. Images shown are volumetric reconstructions of confocal stacks. The various anatomical structures of the larval brain are annotated. VNC refers to the 'ventral nerve chord', which is distinct from dorsal hemispheres of the brain. GFP staining represents the total glial membranes in the larval brains. Scale bar, 100μm. 