The identification and partial cloning by PCR of the gene for tyrosinase-related protein-1 in the Mexican axolotl.

The tyrosinase gene family is currently composed of three members, tyrosinase and two tyrosinase-related proteins, TRP-1 and TRP-2. These three gene products have all been found to act in the synthesis of melanin pigments with the enzyme tyrosinase catalyzing the initial rate-limiting steps. Thus far these genes have primarily been analyzed in higher vertebrates. We have used degenerate PCR primers to isolate a large fragment of an axolotl tyrosinase-related protein. Sequence analysis of the entire 1,057-bp fragment isolated indicates a high degree of similarity to the mouse TRP-1, the product of the brown locus. Phylogenetic analysis supports the conclusion that the fragment isolated corresponds to the axolotl TRP-1 homolog. This is the first TRP-1 gene to be identified in an amphibian species.