Gish regulates single trichome nucleation. (A–B′′) Pupal wing actin-Gal4 FLP-out clones expressing UAS-gish^IR (blue; yellow lines mark clone border) stained with rhodamine-phalloidin (red) and Fmi. (A, A′, B, and B′) No defects in actin polymerization were observed from 26 to 28 h APF (A and A′), whereas multiple prehair nucleation sites can been observed at 30–32 h APF (B and B′, yellow arrowheads). (A′′ and B′′) Fmi localization is asymmetric in gish^IR tissue. (C–D) 32–34 h APF, independently nucleated actin prehairs are observed (C′, yellow arrowheads) and shown in a representative nubbin (nub)-Gal4 UAS-gish^IR TEM section (D, red arrows indicate apical cell surface). Bars: (A–C) 10 µm; (D) 1 µm.