Dominant negative effect of mCul1 overexpression in the wing. (A) Wild-type wing expressing only the GAL4 driver (MS1096/Y). (B) Wings overexpressing mCul1 using the MS1096 GAL4 driver (MS1096/Y;UAS-mCul1/+) are smaller than wild-type. (C) When endogenous levels of Cul1 are reduced by introduction of a mutant allele of Cul1 (MS1096/Y;Cul1k 01207/+;UAS-mCul1/+), wing reduction is enhanced. (D) Co-expression of fly Cul1 (MS1096/Y;UAS-mCul1/UAS-dCul1) rescues wing size to a phenotype indistinguishable from fly Cul1 overexpression alone (not shown). All wings in this and subsequent figures are at the same magnification. Scale bar is 1 mm.