Fig. 1. echinoid mutants display additional es organs and SOPs. (A,B) Scanning electron microscopy of the adult thorax. (A) Wild type. (B) ed^lH23/ed^l(2)k01102 showing additional macrochaetae around each wild-type macrochaete location. (C) Light micrograph of sca-Gal4; UAS-ed thorax. Arrows indicate the positions where macrochaetae should be present. An arrowhead indicates two macrochaetae that have arisen from the same PNC in place of one. (D-J) Confocal microscopy for immunohistochemical detection of (D-G) Sens, and (H-J) Ac (green) and Sens (red) in third larval instar wing discs. (D) Wild type. (E) ed^lH23/ed^l(2)k01102. (F,G) Higher magnification views of scutellar region in (D,E). Note that two SOPs are present at each position (one of the SOPs in F has divided and appears as two adjacent cells). (H) Wild type. (I) ed^lH23/ed^l(2)k01102 showing no difference in Ac level or pattern compared with wild type. (J) sca-Gal4; UAS-ed wing disc at puparium formation. Arrows indicate proneural clusters that have persisted much later than normal in the absence of SOP specification.