Using recombineering methods, the transgene consists of the EGFP-Cre-pA-FrtNeoFrt cassette with 60 bp homology arms upstream and downstream of the TFF2 translational stop codon in exon 4. Three founder lines, all of which displayed a similar pattern of expression throughout various organs (stomach, pancreas, and spleen) were generated. One line 3a was used for all experiments. (J:236280)