Figure 1.

Neuron–glia interaction in the eye imaginal disc. A, B, Confocal images of dissected wild type third instar eye imaginal discs. Neurons are stained using anti-HRP antibodies (blue), glial cell nuclei are labeled using anti-Repo antibodies (red). Anterior is to the top right. In wild type eye imaginal discs migrating glial cells respect a boundary posterior to the morphogenetic furrow (mf) indicated by a white, dashed line. C, Schematic ventral view of an eye imaginal disc. Glial cells populate the eye disc from the optic stalk. The black line indicates the level of the orthogonal section shown in D. D, Glial cells migrate along the carpet cells below the eye imaginal disc (open arrow). Just posterior to the morphogenetic furrow they contact neurons, stop their migration and initiate glial differentiation back toward the CNS (filled arrow). ol, Optic lobe; os, optic stalk; cp, carpet glia; ed, eye disc; mf, morphogenetic furrow; pm, peripodial membrane; Bn, Bolwig's nerve.