LoxP site was inserted into intron 7 together with a self-excision neomycin cassette flanked by Rox sites and a second loxP site was inserted into intron 8. The neomycin cassette was self-excised. Exon 8 was deleted via cre-mediated recombination in the germline. RT-PCR confirmed the in-frame deletion of the central domain (exon 8). Western blot analysis using an antibody against the middle domain confirmed its absence. (J:328987)