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bioRxiv · 10.1101/2020.06.03.132613

Siamese cat tyrosinase has enhanced proteasome degradation and increased cellular aggregation

Niesman, I.
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Abstract

Siamese cats are a notable example of a temperature-sensitive partial albinism phenotype. The signature color-pointing pattern is the result of an amino acid substitution - G302R - in the cysteine-rich domain of feline tyrosinase. The precise mechanism for the loss of tyrosinase enzyme activity due to this mutation is unknown. ObjectiveWe have used a cellular biology approach to begin unravel relationships between feline coloration, behavior and increased risk for feline cognitive dysfunction syndrome. GFP-fusion constructs of wild type domestic short hair tyrosinase and Siamese (G302R) tyrosinase generated to study cellular trafficking, degradation and the propensity for cellular aggregation. Data DescriptionC-terminal GFP G302R expression has reduced Golgi localization, increased cytosolic fractions with reduced calnexin co-localization. N-terminal GFP constructs were retained in the ER, with little to no Golgi associated forms. C-terminal and N-terminal GFP G302R TYR is observed to have increased high molecular weight aggregation following proteasome inhibition.

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Niesman, I.. 2020-06-04. Siamese cat tyrosinase has enhanced proteasome degradation and increased cellular aggregation. https://doi.org/10.1101/2020.06.03.132613

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