Re-integration of DNA into the attP site present in wgKO. The reintegrated sequence is as follows: 1. an FRT cassette containing the full-length, wild-type wg cDNA sequence (including 135 bp of 5'UTR and 1200bp of 3'UTR sequence), 2. sequence encoding a QF driver, and 3. a loxP cassette containing a Disc\RFPmCherry.3xP3 marker. The QF coding region is not expressed due to the presence of the upstream FRT cassette. In addition, a recombined attP/B site is present 5' to the reintegrated sequence.