Figure 2. Generation of Rdh13 knockout mice. A: This is the graphic representation of the Rdh13 gene knockout strategy for the deletion of Rdh13 exons 2 and 3 in embryonic stem cells. Exons are shown in boxes. The targeting vector was designed to delete exon 2 and exon 3. The targeting vector contained a 2.9 kb 5′ arm and 3.2 kb 3′ arm. PGK-Neo and HSV-TK cassettes were used for positive and negative selections, respectively. The genomic positive of the PCR primers for genotyping are indicated by arrows. B: Genomic DNA from ES cell clones was isolated and analyzed by PCR. The successfully targeted embryonic stem cell DNA was amplified into 6.2 kb and 3.5 kb products for the 5′ arm and 3′ arm, respectively. C: The genotype of Rdh13^+/+, Rdh13^+/−, and Rdh13^−/− mice was detected by PCR. D: Rdh13 transcripts in mouse liver from Rdh13^+/+, Rdh13^+/−, and Rdh13^−/− mice was analyzed by reverse-transcription PCR. E: The expression pattern of RDH13 protein in Rdh13^+/+, Rdh13^+/−, and Rdh13^−/− mouse liver was revealed by western blot.