Figure 2

Distinct subsets of cone cells are present in the eye imaginal disc. (A,C,E-G) In wild-type late third instar eye imaginal discs, Pros (A,E,F, magenta), dPax2 (C,F, blue), and Cut (A,C,E, green; G, white) were analyzed by immunostaining. Pros is higher in the equatorial (Eq) and polar (Pl) CCs, while the expression of Cut (E,G, green) and dPax2 (G, blue) are elevated in the anterior (A) and posterior (P) CCs. (B,D) These expression patterns represented in diagrams. Individual ommatidia are circled; anterior is left. (E) In spa^poleye imaginal discs, Cut is mostly absent until the last few most posterior rows, while Pros expression (E, magenta; E', white) initiates in all CC precursors (circles). (F) In pros¹⁷mitotic clones, dPax2 expression (F, blue; F', white) is unchanged between pros mutant (Pros-negative, -/-) and wild-type (Pros-positive, magenta, +/+) tissue. (G) Cut expression is specifically delayed in Eq/Pl CCs (dotted circles) in pros¹⁷mutant tissue (-/-) (individual ommatidial CC clusters are highlighted with dashed circles), whereas in control tissue (+/+), a normal complement of four CCs is observed in comparably positioned ommatidia (solid circles).