Fig. 4.

A founding genetic line of LacI-expressing transgenic axolotls. (A) Protein purified from the tails of two F₀ CAG-LacI mosaic transgenics (35 and 85) shows detectable levels of LacI protein on a Western blot. (B) PCR analysis of genomic DNA from an F₁ juvenile sired by CAG-LacI F₀ #35 (Left) and a wild-type juvenile (Middle), as well as a positive control (pCAG-LacI plasmid, 50 ng). The prod1 promoter sequence served as a positive control for genomic DNA preps (40). (C) Table summarizing process of creating CAG-LacI founder line. Numbers of animals for each category are listed at right. *Only 2/7 animals are males; male gametes can be easily genotyped because sperm is laid in a visible gelatinous packet outside the body. Fertilization is internal and occurs after the female retrieves the spermatophore. Hence, female gametes have not been genotyped.