UAS regulatory sequences drive expression of the dap coding sequence (codon-optimized for Drosophila), in which conserved basic residues within the PIP degron sequence that flank the PCNA protein interaction domain and which have been shown to be important for the interaction with the CRL4[Cdt2] complex, have been mutated to Ala residues (change is RKR to AAA on both sides of the PCNA protein interaction domain).
In individuals with injured gut at late L3W (by the expression of rprUAS.cCb), the expression of dapCRL4.UAS under the control of Scer\GAL4byn-Gal4 leads to decreased adult pyloric cell number.