Clone HTGRS6006_A_G10 from the BACPAC Resources Center, Knockout Mouse Project KOMP repository was used to target embryonic stem cells. The cassette is composed of an FRT site followed by lacZ sequence and a loxP site. The first loxP site is followed by a neomycin under the control of the human beta-actin promoter, SV40 polyA, a second FRT site and a second loxP site. A third loxP site is inserted downstream of the targeted exon 3. Exon 3 is thus flanked by loxP sites. A conditional ready (floxed) allele is created by flp recombinase expression in mice carrying this allele. Subsequent cre expression results in a knockout mouse, removing exon 3. Excision of exon 3 causes a frameshift after the 80th codon. Western blot analysis confirmed the absence of full-length protein in testis.