Melanin’s Journey from Melanocytes to Keratinocytes: Uncovering the Molecular Mechanisms of Melanin Transfer and Processing

Skin pigmentation ensures efficient photoprotection and relies on the pigment melanin, which is produced by epidermal melanocytes transferred to surrounding keratinocytes. While molecular mechanisms of melanin synthesis transport in are now well characterized, much less known about transfer processing within Over past few decades, distinct models have been proposed explain how occurs at cellular levels. However, this remains a debated topic, as up four different proposed, with evidence presented supporting each. Here, we review current knowledge regulation exocytosis, internalization, processing, polarization. Regarding models, discuss these might co-exist regulate skin under conditions, i.e., constitutive facultative or physiological pathological conditions. Moreover, recent that sheds light exocytosis internalization keratinocytes, stored cells compartment propose be named melanokerasome. Finally, state art lead melanokerasome positioning above nuclei forming supranuclear caps shield nuclear DNA from UV radiation. Thus, provide comprehensive overview regulating pigmentation, keratinocytes polarization A better will clarify long-lasting questions field crucial for understanding can shed fundamental aspects organelle biology. Ultimately, novel therapeutic strategies treat hypo- hyper-pigmentation disorders, high socio-economic burden patients healthcare systems worldwide, cosmetic applications.