Common phenotypes in sdk mutant and HA::Sdk-expressing eyes. (Corresponds to Figs. 1 and 4.) Representative examples of cellular defects in sdk mutant eyes and HA::Sdk-expressing eyes that were scored in Figs. 1 G and 4 H and in Fig. 4I. Common defects include missing and extra LCs, misplaced bristles, rosettes, and other intercalation defects and separation of LC–LC contacts that lead to a cell contact forming between 1° cells of adjacent ommatidia.