Figure 5.2.

Time course of Drosophila eye development. A summary of various developmental processes that occur during Drosophila pupal eye development (0–100%). Prior to pupation, in late third instar larva, the antennal/eye disc (A) is easily recognized by strong Cut expression (green) in the antennal portion (anterior, left), and clusters of Elav-positive photoreceptor clusters (blue) in the eye portion (posterior, right) corresponding to individual ommatidial units. Cut-positive cells are also present in the eye-imaginal disc, which represent subretinal glia and CCs precursors. Nonstained cells anterior to the morphogenetic furrow (MF) are retinal progenitors that are still proliferating (see Chapters 1 and 4 for further description). (B) The constricted apical surface of cells within the MF is obvious with E-Cadherin staining (green). In addition, the boundary between the R3 and R4 cell, marked by intense N-cadherin staining (purple), reveals the rotation of the ommatidia relative to the equator that is important for establishing the chiral trapezoid of photoreceptors observed in the adult retina. (C) E-cadherin staining (green) of a whole retina isolated from pupa at ~50% pupation shows the highly regular organization of ommatidia. Inset: A single ommatidium is circled. (D) Photoreceptor-driven Moesin::GFP at 50% pupation shows outer PR axons projecting to the lamina and IPR axons projecting to the medulla. (E) Cut (green) and BarH1(Magenta) specifically recognize the four CC and two primary pigment cell (PPC) nuclei at 50% pupation. (F) Discs Large (Dlg, Purple) highlights the apical contacts of the CCs, PPCs and interommatidial cells in 50% pupal retinas. (G) E-cadherin (green) of the basal surface of the retina shows the petal-shaped distribution of the IOC feet. (H) The bristle cell lineage is composed of four cells which express the transcription factors Cut and Pros, and the neural factor Elav. These nuclei are present at the base of the retina during their development, and eventually move more apically. (I) A scanning electron micrograph of an adult eye pseudocolored to represent the distribution of the pale (blue), yellow(green) and Dorsal Rim Area (DRA; magenta) ommatidia in the eye. (J) Whole mounted adult retina immunostained with Rhodopsin 5 (blue) and Rhodopsin 6 (green) in R8 rhabdomeres. Note the enrichment of Rh6 in the dorsal portion of the retina, corresponding to the dy ommatidia (see text for more detail).