The transgene contains a strong cytomegalovirus (CMV) enhancer followed by the chicken beta-actin promoter; a loxP-flanked beta-galactosidase/neomycin resistance fusion (Bgeo) gene with three polyadenylation signals; the coding sequence of the mouse transducin-like enhancer of split 1, homolog of Drosophila E(spl) (Tle1) gene; and the human alkaline phosphatase, placental (Regan isozyme) (ALPP) gene preceded by an interal ribosome entry site (IRES). In mice doubly transgenic for this and a selected Cre recombinase (cre) transgene, excision of the floxed Bgeo results in whole-animal or tissue-specific co-expression of Tle1 and the ALPP reporter gene.