This is a copper-containing oxidase that functions in the formation of pigments such as melanins and other polyphenolic compounds (By similarity). Catalyzes the initial and rate limiting step in the cascade of reactions leading to melanin production from tyrosine (By similarity). In addition to hydroxylating tyrosine to DOPA (3,4-dihydroxyphenylalanine), also catalyzes the oxidation of DOPA to DOPA-quinone, and possibly the oxidation of DHI (5,6-dihydroxyindole) to indole-5,6 quinone (By similarity). 2 L-dopa + O2 = 2 H2O + 2 L-dopaquinone L-tyrosine + O2 = H2O + L-dopaquinone Binds 2 copper ions per subunit. Forms an OPN3-dependent complex with DCT in response to blue light in melanocytes. Proper trafficking to melanosome is regulated by SGSM2, ANKRD27, RAB9A, RAB32 and RAB38. Glycosylated. Belongs to the tyrosinase family. Snowy stardom - Issue 49 of August 2004