Fig. 4. dRheb overexpression causes increased cell size in the wing. Overexpression of dRheb in the dorsal compartment of the wing disc (using the UASdRheb construct and apGAL4) results in enlargement of the dorsal compartment, as shown by downward curvature of the wing (C,D). When dRheb is overexpressed in the posterior of the wing using UASdRheb and enGAL4, the area of the posterior compartment (B) is larger than that of the control enGAL4 wing (A) (1.0 mm² and 0.73 mm², respectively). Cell density is lower in the posterior compartment of the dRheb-overexpressing (F) than in the control (E) wing (4300 hairs mm^-2 and 6400 hairs mm^-2, respectively), indicating that the dRheb-overexpressing cells are larger. From cell density and area measurements, we find that the number of cells per compartment is not significantly different for dRheb-overexpressing and control wings (6100 and 6100, respectively, anterior; 8900 and 9300, respectively, posterior). Our measurements also reveal apparent compensation for dRheb-driven posterior overgrowth; anterior compartment area is somewhat reduced in UASdRheb,enGAL4 wings relative to control (0.42 mm² and 0.49 mm²) whereas cell density is increased (7300 hairs mm^-2 and 6300 hairs mm^-2).