UASt regulatory sequences drive expression of a mutant form of CtBP that is defective in dimerization (carries the amino acid replacement R171A). The coding sequence is tagged at the C-terminal end with two copies of Tag:FLAG.
posterior crossvein, with Scer\GAL4en.PU
Expressing CtBPDim3.UAS.2xTag:FLAG under the control of Scer\GAL4en.PU results in a posterior crossvein with subtle malformations.