FIG. 1.

Targeted disruption of Car3. (A) Gene deletion strategy. Exons are depicted as open boxes. Filled boxes are selectable markers containing the genes for neomycin resistance (neo) and thymidine kinase (tk). Exons 3, 4, and 5 were replaced with a neomycin resistance gene. Abbreviations for the restriction sites: No, NotI; X, XbaI; S, SpeI: N, NheI; P, PmeI. (B) Southern blot analysis of genomic DNA. Genomic DNA was prepared from littermates obtained by mating heterozygotes. SpeI/PmeI-cleaved genomic DNA from a wild-type mouse (WT) and a mutant mouse (KO) was hybridized to the probe, distinguishing the wild-type allele (6.8 kb) from the targeted allele (8.4 kb). (C) Western blot analysis of liver from 6-month-old male mice. Each lane contained 20 μg of total protein. Car3 was reduced in the heterozygote and absent in the homozygote. M denotes molecular mass standards.