Figure 1.

Schematic representation of melanin synthesis. Melanin is synthetized in melanocytes in response to up regulation of cAMP after α-melanocyte-stimulating hormone (α-MSH) secretion from keratinocytes and activation of melanocortin 1 receptor (MC1R). Increase in expression of microphthalmia-associated transcription factor (MITF) activates expression of enzymatic machinery including tyrosinase and tyrosinase-related protein 1 and 2 (Tyrp1 &2), which regulate the synthesis of melanin within melanosomes. After conversion of tyrosine to melanin it is then translocate to melanosomes in epidermal keratinocytes