Fragment containing the ct wing margin enhancer is inserted upstream of Ecol\lacZHsp70Bb.HZ50.
Ecol\lacZHsp70Bb.HZ50 expression is driven by 2.7kb EcoRI-BamHI fragment of the ct promoter from about coordinate -5 on the ct locus map.
EcollacZct.wHZ transcript is expressed at the presumptive wing margin in the wing disc.