Tyrosinase Sequences

Tyrosinase is an oxidase and a rate-limiting enzyme that regulates melanin production. The enzyme is involved in two reactions of melanin synthesis: the first step is the hydroxylation of monophenol to diphenol, and the second step is the oxidation of catechol to o-diquinone. O-diquinone becomes melanin after a few more steps of reaction. Tyrosinase is a ketone-containing enzyme found in plant and animal tissues that catalyzes the production of melanin oxidized by tyrosine and other pigments, such as peeling or slicing potatoes exposed to the air. Tyrosinase is found in melanosomes of skin melanocytes. In the human genome, tyrosinase is encoded by the TYR gene.

Clinical significance of Tyrosinase Sequences

• Mutations in the tyrosinase gene lead to damage to tyrosinase production, leading to type I eyelid albinism, a genetic disease that affects one in 20000 people.
• Tyrosinase activity is very important. If it is not controlled in the process of melanin synthesis, it will lead to an increase in melanin synthesis. The goal of reducing tyrosinase activity is to improve or prevent diseases related to skin pigmentation, such as chloasma and senile plaques.
• Mutations in the tyrosinase gene lead to impaired tyrosinase production, leading to type I skin albinism, a genetic disease that affects one in 17000 people in the United States.
• Some polyphenols, including flavonoids or stilbenes, substrate analogues, free radical scavengers and copper chelators, have been thought to inhibit tyrosinase. Since then, both the pharmaceutical and cosmetics industries have focused on tyrosinase inhibitors in the treatment of skin diseases.

Conclusion

In humans, the tyrosinase enzyme is encoded by the TYR gene. Tyrosinase is one of the key enzymes in mammalian melanin synthesis. Anti-tyrosinase has been found to be quite specific for melanin lesions such as malignant melanoma and melanin neurofibroma. At present, many tyrosine kinase inhibitors have been developed as antitumor drugs and white blood cell inhibitors. For example, Imatinib is used to treat chronic myeloid leukemia; Sunitinib, developed using early research on VEGF receptors, is also used to inhibit FGF, PDGF, VEGF, and other proteins.

References

1. Poole, A. Z. (2019). TYROSINASE CHARACTERIZATION AND EXPRESSION IN EXAIPTASIA PALLIDA. Georgia Journal of Science, 77(1), 218.
2. Schurink, M., van Berkel, W. J., Wichers, H. J., & Boeriu, C. G. (2007). Novel peptides with tyrosinase inhibitory activity. Peptides, 28(3), 485-495.