The IRES-CreERT2-P2A-EGFP-WPRE-BGH pA cassette was inserted 60~100bp downstream of the TGA stop codon. CreERT2 recombinase and enhanced green fluorescent protein (EGFP) are expressed under the regulatory control of Fcrls 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 Fcrls-positive cells following Tamoxifen induction. In addition to studies of Cre recombinase-mediated gene recombination, this model can also be used for EGFP fluorescent protein tracing studies.