Fig. 4. Prehair emergence in pupal wings with reduced Tsr activity. Confocal images of wild-type and tsr mutant pupal wings stained with phalloidin. Anterior is upwards; distal is towards the left. (A) A wild-type wing shows prehairs initiating as accumulations of F-actin near or at the distal-most vertex of each cell. (B) A similarly staged tsr¹³⁹/tsr^V27Q wing shows prehairs initiated as F-actin accumulations located centrally (dot) or as elongated F-actin structures (asterisk). (C) An older wild-type wing shows prehairs centered over distal cell vertices. (D) A similarly staged tsr¹³⁹/tsr^V27Q wing shows prehairs with abnormal orientations that are similar to the pattern of hairs of the adult wing (Fig. 2B). tsr¹³⁹/tsr^V27Q prehairs are longer, thinner and extend non-distally.