Open AccessA point mutation in the tyrosinase gene of BALB/c albino mouse causing the cysteine → serine substitution at position 85
Author(s) -
SHIBAHARA Shigeki,
OKINAGA Shoji,
TOMITA Yasushi,
TAKEDA Atsushi,
YAMAMOTO Hiroaki,
SATO Michihiko,
TAKEUCHI Takuji
Publication year - 1990
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1990.tb15510.x
Subject(s) - transversion , tyrosinase , point mutation , microbiology and biotechnology , albinism , biology , serine , cysteine , gene , complementary dna , mutation , genetics , locus (genetics) , balb/c , biochemistry , enzyme , phosphorylation , immune system
Murine albinism is characterized by complete lack of melanin pigments in skin and retina. In order to study the molecular basis of albinism, we have cloned and characterized the tyrosinase gene of BALB/c mice ( c/c ). Sequence analysis of this gene reveals a point mutation at nucleotide residue 387 (G → C transversion) causing a Cys→Ser substitution at position 85 in one of the cysteine‐rich domains of the tyrosinase molecule. Since this G→C transversion creates an additional Dde I site, we were able to confirm that this mutation is actually present in BALB/c genomic DNA using DNA amplification techniques. In contrast, both C57BL/6 ( C/C ) and DBA/2 ( C C ) mouse strains carry the G residue at the same position, suggesting that this point mutation is specific for the albino mutation at the c locus. Moreover, we were able to show that the tyrosinase containing Ser‐85 is not functional in transient expression of its cDNA. We therefore suggest that a G→C transversion at nucleotide residue 387 of the tyrosinase gene could lead to the albino phenotype of BALB/c mouse.