scholarly journals Temperature sensitive oculocutaneous albinism associated with missense changes in the tyrosinase gene

2005 ◽  
Vol 89 (10) ◽  
pp. 1383-1384 ◽  
Author(s):  
T Wang
Keyword(s):  
Oculocutaneous Albinism ◽  
Temperature Sensitive ◽  
Tyrosinase Gene

The molecular basis of oculocutaneous albinism type 1 (OCA1): sorting failure and degradation of mutant tyrosinases results in a lack of pigmentation

2001 ◽  
Vol 355 (2) ◽  
pp. 259-269 ◽  
Author(s):  
Kazutomo TOYOFUKU ◽  
Ikuo WADA ◽  
Richard A. SPRITZ ◽  
Vincent J. HEARING
Keyword(s):  
Molecular Basis ◽  
Control Process ◽  
Large Deletion ◽  
Oculocutaneous Albinism ◽  
Temperature Sensitive ◽  
Tyrosinase Gene ◽  
Catalytic Function ◽  
Quality Control Process ◽  
Early Processing

Oculocutaneous albinism type 1 (OCA1) is an autosomal recessive disease resulting from mutations of the tyrosinase gene (TYR). To elucidate the molecular basis of OCA1 phenotypes, we analysed the early processing and maturation of several different types of mutant tyrosinase with various degrees of structural abnormalities (i.e. two large deletion mutants, two missense mutants that completely destroy catalytic function and three missense mutants that have a temperature-sensitive phenotype). When expressed in COS7 cells, all mutant tyrosinases were sensitive to endoglycosidase H digestion, and immunostaining showed their localization in the endoplasmic reticulum (ER) and their failure to be sorted further to their target organelles. Pulse-chase experiments showed that all mutant tyrosinases were retained by calnexin in the ER and that they were degraded at similarly rapid rates, which coincided with their dissociation from calnexin. Temperature-sensitive mutant enzymes were sorted more efficiently at 31°C than at 37°C, and their degradation was accelerated at 37°C compared with 31°C. Thus in contrast to the current concept that mutant tyrosinases are transported to melanosomes but are functionally inactive there, our results suggest that mutant tyrosinases may not be transported to melanosomes in the first place. We conclude that a significant component of mutant tyrosinase malfunction in OCA1 results from their retention and degradation in the ER compartment. This quality-control process is highly sensitive to minimal changes in protein folding, and so even relatively minor mutations in peripheral sequences of the enzyme not involved with catalytic activity may result in a significant reduction of functional enzyme in melanosomes.

The R402Q mutation of the Tyrosinase Gene: Lack of Association with oculocutaneous albinism type 1 (OCA1).

2004 ◽  
Vol 17 (4) ◽  
pp. 427-427
Author(s):  
R. A. King ◽  
J. Pietsch ◽  
M. J. Brott ◽  
S. Savage ◽  
J. P. Fryer ◽  
...  
Keyword(s):  
Oculocutaneous Albinism ◽  
Tyrosinase Gene

scholarly journals A frequent tyrosinase gene mutation in classic, tyrosinase-negative (type IA) oculocutaneous albinism.

1990 ◽  
Vol 87 (9) ◽  
pp. 3255-3258 ◽  
Author(s):  
L. B. Giebel ◽  
K. M. Strunk ◽  
R. A. King ◽  
J. M. Hanifin ◽  
R. A. Spritz
Keyword(s):  
Gene Mutation ◽  
Oculocutaneous Albinism ◽  
Negative Type ◽  
Tyrosinase Gene ◽  
Type Ia

Cloning and sequence analysis of the tyrosinase gene from a patient with tyrosinase-positive oculocutaneous albinism

1992 ◽  
Vol 3 (3) ◽  
pp. 181-185 ◽  
Author(s):  
J MATSUNAGA ◽  
A TAKEDA ◽  
Y TOMITA ◽  
M HARA ◽  
S SHIBAHARA ◽  
...  
Keyword(s):  
Sequence Analysis ◽  
Oculocutaneous Albinism ◽  
Tyrosinase Gene

Polymorphic markers of the human tyrosinase gene for indirect gene diagnosis of tyrosinase-related oculocutaneous albinism (OCA1)

1998 ◽  
Vol 16 ◽  
pp. S149
Author(s):  
Jun Matsunaga ◽  
Muneo Tanita ◽  
Miwako Dakeishi-Hara ◽  
Eriko Nakamura ◽  
Yoshinori Miyamura ◽  
...  
Keyword(s):  
Oculocutaneous Albinism ◽  
Polymorphic Markers ◽  
Gene Diagnosis ◽  
Tyrosinase Gene ◽  
Human Tyrosinase

Prenatal diagnosis of oculocutaneous albinism by tyrosinase gene analysis

1993 ◽  
Vol 6 (1) ◽  
pp. 37
Author(s):  
Hiroshi Shimizu ◽  
Hironori Niizeki ◽  
Kaoru Suzumori ◽  
Ryoji Aozaki ◽  
Ryuji Kawaguchi ◽  
...  
Keyword(s):  
Prenatal Diagnosis ◽  
Oculocutaneous Albinism ◽  
Gene Analysis ◽  
Tyrosinase Gene

Tyrosinase gene analysis in Japanese patients with oculocutaneous albinism

2004 ◽  
Vol 35 (3) ◽  
pp. 215-220 ◽  
Author(s):  
Maki Goto ◽  
Kazuko C. Sato-Matsumura ◽  
Daisuke Sawamura ◽  
Koichi Yokota ◽  
Hideki Nakamura ◽  
...  
Keyword(s):  
Japanese Patients ◽  
Oculocutaneous Albinism ◽  
Gene Analysis ◽  
Tyrosinase Gene
Sign in / Sign up

Export Citation Format

Share Document