Molecular cloning and sequence analysis of a chicken cDNA encoding tyrosinase-related protein-2/DOPAchrome tautomerase.

We have cloned and sequenced a chicken cDNA encoding an l-DOPAchrome tautomerase (DCT) from an embryonic melanocyte cDNA library. The chicken DCT gene encodes a deduced protein of 516 amino acids (aas) and shares 69.2% and 69.9% aa sequence identity with the deduced mouse and human DCT proteins, respectively. Northern blot hybridisation analysis reveals a DCT transcript of 3.5kb in RNA from the retinal pigment epithelium (RPE) of chick embryos. Genomic Southern blot hybridisation analysis suggests that the chicken DCT gene consists of several introns and spans between 15 and 30kb of the chicken genome. This study completes the sequencing of all the members of the chicken tyrosinase-related protein gene family and provides evidence that this gene family is conserved between avians and mammals.