Efficiency and genotype specificity of Cre-induced mutant allele mRNA conversion (MAC) in tissues after tamoxifen treatment in Gα
mice. A Representative chromatograms of sequenced PCR products from mRNA purified from hearts of tamoxifen-treated mice (50 mg/kg i.p. on five consecutive days). Mice lacking Cre (Cre-ERT2-) showed no evidence of the TAGT sequence expected for G184S mutant mRNA (top chromatogram). For mice expressing Cre (Cre-ERT2+), the percentage conversion to the mutated sequence (% MAC) was higher in mice that were homozygous for the G184S mutation (Gαi2
fl-G184S/fl-G184S, lower chromatogram) than in heterozygous (Gαi2
+/fl-G184S, middle chromatogram) animals. B The extent of recombination was higher in blood and liver than in other tissues with heart showing approximately 80% MAC in homozygotes. Values are expressed as the mean (±SE, n = 3) of the percentage of the mutated allele determined from the added peak heights of the three changed bases (see Methods).