TALEN based technology was used to insert the following construct into the target gene. A loxP followed by lox2272 was inserted upstream of exon2 and its start cocon. This was followed by an FRT flanked neomycin/kanamycin construct in reverse orientation. This was followed in turn by an EGFP/Satb1 3'UTR, again in reverse orientation. Finally, a second loxP followed by lox2272 was inserted. Cre expression will invert the sequence between loxP sites allowing expression of EGFP. (J:206457)