The TGA stop codon was replaced with the "P2A-CreERT2-WPRE-BGH pA" cassette. CreERT2 recombinase is expressed under the regulatory control of Aqp5 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 alveolar type I cells, salivary gland alveolar cells, and gastrointestinal stem cells following Tamoxifen induction.