Fig. 1

Organization of the dystroglycan gene and position of the floxed Neo cassette. a Schematic representation of the Dag1 ^+/+ allele, the targeting vector, the Dag1 allele after incomplete homologous recombination (Dag1 ^Neo) and the neo-deleted allele (Dag1 ^ΔNeo). The 5′ arm of the construct consisted of a 3.2 kb fragment amplified from the Dag1 intron. The 3′ arm was 4 kb in length and consisted of the exon 3′ region, harbouring four mutations (red asterisks) hitting the α/β-DG interface, and flanked by intronic sequences and the 3′-UTR, respectively. A XhoI (X) site in the 5′ arm was mutated for cloning purposes. The floxed neomycin cassette (Neo) and the Herpes simplex thymidine kinase (TK) acted as positive and negative selection markers, respectively. Selected restriction enzyme cleavage sites are indicated above the gene (B: BamHI; H: HindIII and X: XhoI). Primers used for genotyping are also indicated as black arrows. b A representative PCR genotyping analysis of the Dag1 ^Neo/+ mouse. The PCR product was amplified from genomic DNA using primers spanning the Neo cassette region