Polk^tm1.1Rsky

A loxP-flanked exon 6 and downstream floxed neo cassette were removed by crossing chimeric animals to a cre deleter strain resulting in the deletion of essential catalytic residues apartate 197 and glutamate 198, as well as a frameshift mutation via splicing from exon 5 to exon 7. RT-PCR analysis of testis RNA confirmed the presence of a shorter transcript in mutant animals. Northern blot analysis showed that the mutant transcript is expressed at 5 times less than the wild-type allele. (J:80212)