Abstract
Melanin, the end products of complex multistep transformations of L-tyrosine, are multifunctional biopolymers. Synthesis of melanin (melanogenesis) is a highly regulated and complex event occurring within melanocytes and melanoma cells. Although several factors have been known to participate in the regulation of melanogenesis, the precise mechanism (s) underlying the melanogenic process remains to be defined. On the other hand, phospholipase D (PLD) cleaves phosphatidylcholine in response to a variety of cell stimuli to generate phosphatidic acid which is thought to regulate a variety of cellular responses. Our recent study has demonstrated that PLD1 exerts a negative regulatory role in the melanogenic process by suppressing the expression of melanogenic enzymes leading to the decreased activity, probably through the PLD1/ mammalian target of rapamycin (mTOR) pathway.
