Figure 3.

Drosophila Par-1 is required for proper eye development and photoreceptor differentiation. (A–C) Adult heads with eyes in which various transgenes were expressed: ey-Gal4 in a y w background (A), ey-Gal4 driving UAS-par-1 RNAi-1 (B), or UAS-par-1 RNAi-2 (C). Expression of either par-1 RNAi-1 (BL#35342) or par-1 RNAi-2 (BL#32410) by ey-Gal4 causes small eyes (B and C). (D–F) ERGs of flies shown above. Arrows indicate the loss of on- and off-transients of ERGs. Quantification of eye sizes (G) (n=10; error bars represent ±SEM, ∗∗∗P<0.001, t-test) (H and I). Quantification of the ERG amplitude (H) and on-transients (I) of ERG traces in (D–F) (n=13; error bars represent ±SEM, ∗∗∗P<0.001, t-test). (J–O) Expression of par-1 RNAi-1 driven by ey-Gal4 significantly reduces the levels of Par-1 in eye discs. (J and K) Eye imaginal disc is stained for Par-1 (red) and the pan-neural marker Elav (white). Par-1 is ubiquitously expressed in the developing eye disc (L). The expression of Par-1 is severely reduced in eye disc of ey > UAS-par-1 RNAi-1 (M). (N and O) Knockdown of Par-1 results in a dramatic reduction in photoreceptor numbers. Elav staining in wild-type control discs (N). Knockdown of Par-1 severely reduces the number the photoreceptors in developing eye disc. Scale bars, 50  μm (J–O).