Fig. 4. Targeted expression of Tsh genes in the fly eye cause the same defects as misexpressed tsh. (A,C) Ectopic eye development in dpp>tsh (A) and dpp>Tsh3 (C) ventral to the normal eye in the pharate adult raised at 25°C (arrows). About half dpp>Tsh1 (not shown), dpp>Tsh3 flies (n=36 and n=41 respectively) and one third of dpp>Tsh2 flies (n=57, not shown) show ectopic eye development. (B,D) Scanning electron micrographs of the heads of ey>tsh (B) and ey>Tsh2 (D) flies raised at 25°C showing impaired eye development. A wild-type eye is shown in the inset in B. About one third of ey>Tsh1 (n=45, not shown) and ey>Tsh3 (n=29, not shown), and 15% of ey>Tsh2 (n=63) flies do not develop eyes. tsh expression leads to eye defects in more than 80% of the flies (dpp>tsh, n=28 and ey>tsh, n=33).