Decoding melanogenesis: An integratedview of enzymatic, genetic, and signalingregulation

Abstract

Melanogenesis is a complex and tightly controlled biological process responsible for producing melanin pigment that
gives skin its color and protects it from ultraviolet radiation damage. This review summarizes the main molecular
pathways and mechanisms governing melanin production, integrating cellular, biochemical, and genetic aspects.
Melanin is produced in melanocytes within specialized organelles called melanosomes, with enzymes such as Tyrosinase,
Tyrosine-related protein 1 (TRP-1), and Tyrosine-related protein 2 (TRP-2), playing critical roles in melanogenesis
and determining whether melanin is eumelanin or pheomelanin. The master regulator of melanocyte functions is
the microphthalmia-associated transcription factor (MITF), which controls cell viability, cell differentiation, and the
expression of melanogenic enzymes. Further, the processes are also modulated by various signaling pathways such
asCyclic adenosine monophosphate (cAMP)/Protein kinase A (PKA), Mitogen-activated protein kinase (MAPK),
Phosphoinositide 3-kinase (PI3K)/Protein Kinase B (AKT) and Wingless/Integrated–Beta-catenin signaling pathway
(Wnt) Bita-catenin in response to hormones and environmental conditions. Dysregulation of the intricate network
governing melanogenesis results in pigmentation disorders (hyperpigmentation or hypopigmentation) that should be
efficiently treated with targeted therapies that require a good understanding of the mechanisms.