Figure 3

Sce and Scm are required to maintain repression of Sens in R7s. (A–B') Representative mosaic ommatidia containing homozygous R7 clones created by GMR-FLP/MARCM (green; arrows) at 24 h APF. Scale bar is 5 μm. (A,A') Wild-type (homozygous FRT82) R7s do not express Sens (dashed outline). Arrowheads point to Sens in R8s. (B,B') Sce mutant R7 misexpressing Sens (dashed outline). (C) Quantification of Sens expression in Sce and Scm mutant R7s. Error bars represent SEM. No Sce mutant R7s express Sens in late larval (L3) eye discs (0/551 R7s in 5 eye discs). 52.1% ± 3.7% (n = 10 retinas) of Sce mutant R7s express Sens at 24 h APF and 65.5% ± 5.4% (n = 7 retinas) do so at 48 h APF. No Scm mutant R7s express Sens at L3 (0/447 R7s in 3 eye discs) or 24 h APF (0/108 R7s in 3 retinas). 16.3% ± 1.9% (n = 5 retinas) of Scm mutant R7s express Sens at 48 h APF.