Figure 1.

Hypomethylated cortical cells are detected in Emx1-cre; Dnmt1^2lox/2lox mutants throughout the normal life span (A) LacZ histology pattern shows brain regions with Dnmt1 gene deletion via the R26R reporter (ref. 20). (B) The recombination efficiency was analyzed by Southern blotting analysis. The percentages of Dnmt1 gene deletion are derived from the ratio of recombined null allele (1lox) over the sum of functional Dnmt1^2lox (2lox) and 1lox alleles. (C) The graph view of the efficiency of Dnmt1 gene deletion in control and mutant mice from E11.5 to adulthood at 1.5 years old. (D) Southern blot analysis of DNA methylation in dorsal cortex. DNA was digested with methyl-sensitive enzyme HpaII (CCGG) and was hybridized to an IAP probe. CON, Emx1-cre; Dnmt1^210x/+ control; MUT, Emx1-cre; Dnmt1^210x/210x mutant; Ctx, cortex; str, striatum.