Fig. 7. Phenotype of adult wings following the misexpression of modified/mutated forms of brk. UAS-brk transgenes (see Fig. 2D) were driven by en-Gal4 in the posterior compartment and C765 ubiquitously (C765 is weaker than en-Gal4). (A) Wild-type wings shaded to indicate the expression domains of the Gal4 drivers. (B-F) The activity level of different Brk proteins was classified into five categories from `++++' (full, wild-type level) to `–' (no repressor activity; see Materials and methods); examples of each category are shown, for comparison, the temperature must be taken into account (Gal4 is cold sensitive). (B) Full activity of 3PF3 (wild type). With en-Gal4, no animals survived to adult; with C765 the wing size is drastically reduced at 20°C. (C-F) Mutated/modified Brk proteins have weaker activity than wild type. (C) Stop1, 20°C (top); CM, 20°C (bottom). (D) 3M, 25°C (top); 3M, 30°C (bottom). (E) A2, 30°C. (F) NLS, 30°C (top); F124, 30°C (bottom). At high temperatures, ectopic veins are produced with F124, which we attribute to gain of function, as it has no effect on Brk target gene expression.