Targeted disruption of the RapGEF2 gene. Strategy for generating the RapGEF2 conditional targeting vector. (A) Schematic representation of the mouse RapGEF2 genomic sequence, targeting vector, neo, cko, and ko alleles. The targeted exon 18 and its adjacent exon 19 are in red. After electroporation of the RapGEF2 targeting vector, embryonic stem (ES) cells and then the neo mice were screened by Southern blotting (B). After crossing the neo mice sequentially with the flp and β-actin^cre mice, the RapGEF2^+/− mice were screened by Southern blotting (C). PCR strategies were used to identify the RapGEF2^+/+, RapGEF2^cko/+, and RapGEF2^cko/cko mice (D), RapGEF2^+/+, RapGEF2^+/−, and RapGEF2^−/− embryos and mice (E), and Cre transgenic mice (F). The RapGEF2^+/− mice were fertile and apparently normal, compared with the wild-type (RapGEF2^+/+) mice.