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Fig. 1. hh functions synergistically with ey to induce Eya
expression and photoreceptor differentiation. (A-F) All panels show wing discs
(anterior towards the left and dorsal upwards) with different combinations of
UAStransgenes driven by the 30A-GAL4 driver. The expansion of the
wing disc in all panels is a result of overexpression of either dpp
or hh, and reflects the capacity of these genes to induce growth and
proliferation of imaginal disc cells. (A,D) ey and dpp
co-expression in a ring around the wing pouch induces Eya expression (A) and
photoreceptor differentiation, but only in the posterior compartment.
Endogenous Eya expression in the wing disc appears as vertical stripes of
staining in the anterior and posterior compartment (arrowheads in A). (B,E)
When ey and hh are co-expressed, Eya is expressed (B) and
photoreceptors differentiate, but only in the anterior compartment. (C,F)
Overexpression of ey, dpp and hh together induces Eya
expression (C) and photoreceptors in both compartments of the disc pouch.
(D-F) Photoreceptor differentiation is visualized by an antibody to the
pan-neuronal protein Elav.