Mutations in dopachrome tautomerase (Dct) affect eumelanin/pheomelanin synthesis, but do not affect intracellular trafficking of the mutant protein.

ABSTRACT: Dopachrome tautomerase (Dct) is a type I membrane protein and an important regulatory enzyme that plays a pivotal role in the biosynthesis of melanin and in the rapid metabolism of its toxic intermediates. Dct-mutant melanocytes carrying the slaty or slaty light mutations were derived from the skin of newborn congenic C57BL/6J non-agouti black mice and were used to study the effect(s) of these mutations on the intracellular trafficking of Dct and on the pigmentation of the cells. Dct activity is 3-fold lower in slaty cells compared with non-agouti black melanocytes, whereas slaty light melanocytes have a surprisingly 28-fold lower Dct activity. Homology modelling of the active site of Dct suggests that the slaty mutation [R194Q (Arg194-->Gln)] is located in the active site and may alter th

SUBMITTER: Costin GE 

PROVIDER: S-EPMC1276922 | biostudies-literature | 2005 Oct

REPOSITORIES: biostudies-literature