Figure 2

B3gnt5 gene targeting in ES cells. A. The targeting vector was produced by cloning a neo resistance cassette into exon 4 of the mouse B3gnt5 gene. The construct was flanked by two genomic arms of 1.7 and 3.6 kbp. A genomic probe located just outside of the targeted region was used to detect homologous recombination. B. Genomic Southern blotting of ES cell clones. Genomic DNA of wildtype (WT) ES cells and of two ES cell clones bearing a homologously recombined B3gnt5 allele (5B5 and M20) were digested with EcoRI and hybridized to the genomic probe. C. Genotyping of wildtype (+) and targeted (-) B3gnt5 alleles by PCR as described in the Materials and Methods section.