Fig. 4. EdExt has dominant-negative activity. (A) Control wing of UAS-EdExt/+ fly. (B) UAS EdExt/69B GAL4 fly wing have irregular wing vein II. (C) T80 GAL4/+; UAS-EdExt/+ fly wing exhibits irregular wing vein II and rare notches (indicated by the bracket) in the distal wing margin. (D) Partial dorsal thorax of control (UAS-EdExt/+) fly showing the normal number of sensory bristles on the scutellum. (E) Scutellums of T80 GAL4/+; UAS-EdExt/+ flies show extra sensory bristles (indicated by arrowheads). The extra sensory bristle phenotype is more evident when pnr GAL4 is used to mediate EdExt expression. A loss of epithelium is also noticeable (F). (G) Magnification of a part of the mesothoracic region of the thorax in F. The microchaetae are missing (asterisk) or quadrupled (arrows).