The transgene generated by using a BAC clone containing the mouse gene, PR23-421H21. The sGFP (a 300-bp sequence coding for a portion of EGFP) gene was inserted into the exon 2 of in the BAC clone. The 3-UTR was replaced by the polyA sequence (250 bp) of SV40, and intron 1 had been excised. (J:193411)