Figure 2.

Induction of ectopic photoreceptor cells and eyeless by Notch signaling. (a) Anti-β-galactosidase (β-gal) antibody staining of a UAS-N^act UAS-lacZ ey-GAL4 eye-antennal disc. Activation of the lacZ reporter reflects the distribution of constitutively activated Notch protein. Arrowhead indicates hyperplastic portion. (b) Immunostaining of same disc as in a with antibody against the neuronal marker ELAV. In the hyperplastic portion (arrowhead) ectopically induced photoreceptors. (c) Anti-β-galactosidase antibody staining of a UAS-N^act UAS-lacZ ey-GAL4 eye antennal disc. Activation of the lacZ reporter reflects the distribution of N^act protein. Arrowheads indicate areas of strong lacZ expression. (Bar indicates 50 μm.) (d) Immunostaining of same disc as in c with antibody against EY. Ectopic EY expression is induced in the areas of strong lacZ expression (arrowheads).