Ugt1^tm1.1Afmu

A loxP site was inserted upstream of exon 4, a single base pair deletion was introduced in exon 4, and a loxP site and FRT flanked neo cassette were inserted downstream of exon 4 via homologous recombination. Flp mediated recombination removed the neo cassette. The single base pair deletion in exon 4 results in a frameshift mutation and a premature stop codon. Northern blot analysis showed a decrease in mRNA expression to 22% of wild-type in homozygous mice at P5. No protein expression was detected by western blot analysis of liver protein extracts from homozygous mice. (J:182805)