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Fig. 2. R8 photoreceptors are frequently twinned in ed mutants. (A-E)
Confocal microscopy for immunohistochemical detection of Ato (green) and Sens
(red) (A,C,E), and Ato (green) and Boss (red) (B,D) in third larval instar eye
discs. (A,B) Wild type. (C,D) ed4.12/ed4.12.
(E) edlH23/Df(2L)ed-dp. A twinned R8 precursor pair is
indicated by the arrow. (F) Expression of an R7 enhancer trap (R70-9) in an
ed4.12 mutant background. Immunohistochemical detection of
Sens (red) and ß-galactosidase (green). The open arrow indicates a
wild-type R8/7 pair. The closed arrow indicates twinned R8s with associated
twinned R7s. The arrowhead indicates a twinned R8 with a single R7. Anterior
is towards the left in all figures.