An IRES linked to an EGFP-cre fusion protein and an FRT-flanked neomycin resistance cassette were introduced immediately after the Zbtb16 (Plzf) stop codon (in exon 7) via homologous recombination in C57BL/6J-derived embryonic stem (ES) cells. Mice were bred to ACTB-FLPe animals to excise the neomycin cassette and create the PLZF allele. (J:204428, J:205609)