Sequence for the tdTomato reporter gene, 2A self-cleavage peptide sequence, the human diphtheria toxin receptor (HBEGF) cDNA, a loxP site, the mouse Ace (angiotensin I converting enzyme (peptidyl-dipeptidase A) 1) promoter, the cre recombinase gene, a neomycin resistance gene cassette, and a second loxP site, was inserted in the 3' UTR 14 bp downstream of the stop codon via homologous recombination. Cre-mediated recombination in the male germline removed the cre+neo cassette. (J:217638)