TYRP1

TYRP1 stands for tyrosinase-related protein 1, a gene that encodes a melanocyte enzyme belonging to the tyrosinase family. The protein is expressed in melanocytes and retinal pigment epithelium and localizes to melanosomes, the organelles where melanin is produced. It is co-expressed with other melanogenic enzymes such as tyrosinase (TYR) and TYRP2, and its expression is regulated by MITF, a key transcription factor in melanocyte biology.

Functionally, TYRP1 is involved in the later stages of melanin biosynthesis. It is associated with dopachrome tautomerase activity in the eumelanin pathway, aiding conversion steps that influence the ratio of eumelanin pigments. The enzyme may also contribute to melanosome maturation and help stabilize other enzymes involved in pigment production, although the exact in vivo roles can be context-dependent.

Genetics and phenotype vary with TYRP1. In humans, variation in TYRP1 contributes to differences in pigmentation across populations, affecting hair, skin, and eye color. Pathogenic variants in TYRP1 cause oculocutaneous albinism type 3 (OCA3), a condition characterized by reduced melanin in skin and hair and associated visual abnormalities. The phenotypic severity of OCA3 can vary among individuals and populations.

In research, TYRP1 has been studied in model organisms; Tyrp1-deficient mice show altered coat color and changes in melanosome structure, providing insight into melanogenesis and pigmentary disorders. TYRP1 is part of a gene family with TYR and TYRP2, all contributing to the melanin production pathway.