Fig. 1. Expression pattern of en-RFP-Moesin and ptc-GFP-Moesin in the dorsal epithelium. (A) Schematic illustrating construction of the fly line, transgene expression pattern and dorsal trichome pattern. (B,C,F) Images of embryos expressing en-RFP-Moesin (red) and ptc-GFP-Moesin (green). (Bi-iii) Dorsal view of embryos at the start (i), midway through (ii), and shortly after completion (iii) of DC. (Ci-iii) Time course of the latter stages of DC in a live embryo. Misplaced ptc-GFP-Moesin-expressing cells (asterisks in i) are present at a conserved position at the leading edge of the en domains of all segments shown. (D) Bar chart showing proportion of embryos with misplaced ptc-GFP-Moesin-expressing cells in each segment. (E) Dorsal view of stage 16 embryo expressing GFP-Moesin (green) constitutively and RFP-Moesin (red) under control of en-Gal4. Pairs of cells in the P compartment not expressing RFP-Moesin are indicated by arrowheads. (Fi-iv) Images from Movie 1 (see Movie 1 in the supplementary material) showing cell rearrangements during DC that lead to the presence of the misplaced ptc cell (asterisk) in the en domain. Scale bars: 10 µm.