Figure 5. BAC Tg–mediated rescue of the Ren-1^C–null mouse.

(A) Breeding strategy for introducing a single copy of WT or mut Ren-1^C BAC Tg into the Ren-1^C–null genetic background. 2&1^D, endogenous Ren-2 and Ren-1^D loci; 1^C-Tg, Ren-1^C BAC Tg; 1^C-null, targeted Ren-1^C locus; 1^C; endogenous Ren-1^C locus. (B) Southern blot analysis for discriminating the genotype. Tail-tip DNA was digested with BamHI and hybridized with a Ren-1^C genomic DNA probe (PstI-XbaI fragment around exon 5), which hybridized to diagnostic bands from the Ren-2 (7.2 kb) and Ren-1^D (6.7 kb), Ren-1^C or Tg (5.8 kb), and Ren-1^C–null (3.7 kb) loci. (C) Northern blot analysis of renin gene expression in the compound mice. Total RNA from the kidney of 2-month-old animals was hybridized with a mouse Ren-1^C cDNA probe (KpnI-NcoI fragment, 820 bp) and mouse Gapdh cDNA probe (453 bp, nt 565 to 1,017; MUSGAPDH, GenBank accession no. M32599). endo, endogenous Ren-1^C genotype. (D–F) PRA (8-week-old), AI contents (8-week-old), and SBP (6-week-old) of the compound mice. Data are means ± SD; n is shown below each bar. (G) Renin mRNA levels in the testis, ovary, SMG, and adrenal of WT and mut RP-2 compound mice (8-week-old). Graph shows means ± SD; n = 3–4 per group. Expression values in the WT male animals were arbitrarily set at 1.0. Roman numerals refer to the genotypes shown in A.