An approximately 6.7kb per promoter fragment and the per 5'UTR are fused upstream of an FRT cassette that contains the mCherry coding sequence and three stop codons. The pLUC coding sequence is present downstream of the FRT cassette. In the absence of FLP recombinase, mCherry is expressed. If the FRT cassette is excised using FLP recombinase, mCherry is removed and pLUC is expressed instead.