Fig. 6. Eyes absent and sine oculis have complementary expression patterns to Wingless. (A-C) Expression of wg-lacZ (green) and Eyes absent protein (red and white in right-hand panels) during third instar eye disc development. (A) In the early third instar eye disc, before initiation of the morphogenetic furrow, Wingless is expressed in the anterior lateral margin of the eye disc, whereas Eyes absent is expressed throughout the eye primordia. (B) In the mid-third instar eye disc, when the morphogenetic furrow has started its posterior to anterior progression, the expression pattern of both genes remains similar. (C) A basal view (single confocal section) of a late third instar eye disc, showing that Eyes absent is missing from the anterior lateral margin where Wingless is expressed. Note that in posterior regions some overlap is seen (indicated by yellow staining). (D) Expression of sine oculis-lacZ (red, white in right-hand panels) and Wingless protein is precisely complementary in the anterior region, but slightly overlap in the posterior lateral region (single confocal section).