ed staining can be found in floor cells, but not in adjacent br-positive roof cells.

During embryogenesis, ed is initially detected uniformly at the apical domain of all epidermal and amnioserosa cells. Just before dorsal closure, levels of ed begin to decrease in the amnioserosa cells. Cells that abut the DME cells are the first to exhibit complete loss of ed. By stage 13 (epithelial sweeping phase), ed is absent from all amnioserosa cells and remains absent during stage 14 (zippering phase) and stage 15 (termination phase).

ed is uniformly distributed on the AJs in all cells anterior to, and within, the morphogenetic furrow. Posterior to the morphogenetic furrow, ed remains uniform in the interommatidial cells but is greatly but not completely downregulated in the R8/R2/R5 photoreceptor precurors and, to a lesser extent, in the R3/R4 cells of the ommatidial precluster.

ed is detected in trachea from embryonic stage 10 until the end of embryogenesis. It is present in the fusion cells from stage 14 on. ed expression levels among the tracheal cells, including the fusion cells, appears uniform during invagination, branching, and fusion of the tracheal repeats into a continuous tubular network.

High levels of ed protein localize at the apical surface of all cells in the MF and through row 1. In rows 3 and 4, ed is reduced specifically within the cells that will soon begin to rotate, making the photoreceptor clusters appear as holes within the imaginal disc epithelium. This staining pattern persists until row 7. High ed levels are observed in photoreceptors R1, R6 and R7 when they are recruited into the growing ommatidium in rows 5/6. A dramatic shift in the relative levels of ed within the ommatidia and in the interommatidial cells occurs when cone cells are recruited. ed becomes prominent in two bands, one at the interface between the cone cells and the photoreceptors and a second at the interface between the cone cells and the interommatidial cells.