Figure 1.

Generation of an Scnn1g hypomorphic allele. A: schematic of the wild-type (wt) and transgenic Scnn1g locus [encoding the epithelial Na⁺ channel (ENaC) γ-subunit]. The genomic region corresponding to the targeting construct is represented as a hatched box. Dark green boxes represent exons. Bars with * represent the radiolabeled 5′-probe used for Southern blot. †Position of the 3′-probe. These are external to the targeting construct (shown as the hatched region). Restriction sites used for Southern blot are marked. B: homologous recombination of the 5′-arm was confirmed by Southern blot of Sac1-digested embryonic stem cell genomic DNA with the 5′-probe (†). Correct recombination of the 3′-arm was confirmed following Nde1 digest of genomic embryonic stem cell DNA, followed by Southern blot with the DNA probe shown (*). +Clones with correct homologous recombination in a single chromosome. Chr, chromosome; Neo, neomycin resistance cassette; γENaC-V5, cDNA for the ENaC γ-subunit.