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How do melanocytes produce skin pigment?

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Learn how regenerative properties of the skin helps to protect the human body from the external environment — human skin Human skin, whose cells are generated continuously by the body, serves as a protective barrier between the inside of the human body and the environment.

Melanocytes produce skin pigment through a specialized biochemical process that begins with the oxidation of the amino acid tyrosine, a reaction facilitated by the enzyme tyrosinase.21

Following this initial step, the synthetic pathways diverge to create two distinct types of melanin:
* Eumelanin: A dark brown pigment.21
* Phaeomelanin: A pale red or yellowish pigment.21

Once synthesized, these pigment granules are transferred to neighboring keratinocytes via long, branching extensions called dendrites. This functional grouping of a melanocyte and its associated keratinocytes is known as an epidermal melanocyte unit. Within the keratinocytes, the melanin granules often position themselves above the cell nucleus, forming a protective shroud that helps shield the cell from damage caused by ultraviolet radiation.21

The activity of these cells is regulated by factors such as melanocyte-stimulating hormone, which can increase melanin production in response to stimuli like sunlight exposure.23