Figure 3.

PlexA interacts genetically with sema1a. R-cell axonal projection pattern in third-instar larval eye–brain complexes was visualized with MAb 24B10 staining. A, Wild type. B, Normal R-cell projection pattern was observed in sema1a heterozygotes. C, Larvae in which the level of PlexA was specifically knocked down in the eye displayed a mild phenotype. D, Reducing the dosage of sema1a by 50% in PlexA knockdown larvae increased both penetrance and severity of the phenotype. Scale bar, 20 μm.