Figure 1. Generation of an E2f1^S29A/S29A knock-in mouse model.

(a) Schematic of gene targeting construct and knock-in strategy (b) ES cell clones with the correctly targeted E2f1 allele were detected by Southern blot analysis of genomic DNA digested with BamHI and AviII. The wild type allele produces a 14 kb band while the knock-in allele produces a 6 kb band (lanes 2, 4 and 5). (c) Genotyping of mouse litters by PCR using primers across the remaining Frt site. The wild type allele without Frt produces an approximately 200 bp band and the knock-in allele produces a band of approximately 300 bp.