The PBac{3xP3-EYFP,p-tTA-K10} construct was designed for use as an enhancer construct, containing at its 3' end a potential enhancer trap sequence that consists of a minimal P\T promoter and first intron fused upstream of tTA driver sequence. However, only 2% of PBac{3xP3-EYFP,p-tTA-K10} insertions functioned as an enhancer trap in a screen.