The "IRES-CreERT2" cassette was inserted ~60~100 bp downstream of the TGA stop codon. CreERT2 recombinase is expressed under the regulatory control of Cldn18 gene elements. This model is a Tamoxifen-inducible Cre mouse, and when crossed with mice containing loxP sites, the offspring mice are expected to undergo sequence recombination between loxP sites mediated by Cre recombinase in the lungs, stomach, and intestines following Tamoxifen induction.