Figure 2

Phenotypes caused by expression of Dlk1 resemble Notch loss-of-function and are enhanced by Notch mutations. (A) Diagram showing domain of Ptc::Gal4 expression (blue) in the wing, red arrows indicate regions scored for Table 1 (m = margin). (B) Wild-type wing. (C-F) Wings expressing SM-Dlk (C,D; 2 copies of transgene) and M-Dlk (E,F; 1 copy of transgene). (G,H) Heterozygous N^55e11/+ wings, phenotypes of M-Dlk expression (H) are enhanced. (I,J) Effects of SM-Dlk at 25°C (I,I') and 30°C (J,J') on cell number and cell size, cell number is reduced by stronger expression, (I,J; fewer cells between L3/L4, red arrows) and cell size is increased (I'J'; evident from spacing of the trichome hairs, e.g. red lines). (K-M) Ectopic sensory bristles (arrows, wild-type has 4 sensory bristles) in the scutellum of SM-expressing (K), and M-Dlk expressing flies (L,M). Ectopic bristles are enhanced when Notch levels are reduced (N^55e11/+; M). (N) Graph summarising the phenotypes obtained with different combinations at 25°C. (SM-Dlk was present in 2 copies).