7.5kb genomic sequence from fru (BACPAC BACRP98-2G21, includes a conserved dsx motif (DSX1) and the P4 promoter) is placed upstream of a nuclear GFP reporter. 7 core nucleotides of DSX1 are replaced by G nucleotides in this construct, along with mutation of two other sites that weakly resemle the dsx consensus motif (DSX2 and DSX3).