Il13^{tm1(YFP/cre)Lky}

A targeting construct containing a bicistronic reporter/recombinase cassette (loxP-Neo-loxP IRES-YFP-cre cassette and DTA negative-selection cassette with appropriate homology arms) was electroporated into ES cells containing a Prm-cre transgene. Homologous recombination resulted in insertion of the IRES-YFP-cre sequence between the translational stop codon and the 3'UTR of the Il13 gene, preserving the normal function of the gene yet allowing expression of the YFP/cre fusion protein. The floxed Neo cassette was deleted in the male germline (by Prm-cre) when chimeras were bred to wild-type females. (J:161387)