Melanocytes, in the basal epidermis of the skin, control skin pigmentation through synthesis of melanin.
Classical and Non-Classical Regulation of Melanin Production
Skin exposure to sunlight (ultraviolet radiation) increases the production of melanin through activation of the MC1R receptors and can result in darker colored skin (tanning). Repeated exposure to UVR can lead to darker skin over time.
New data from Natale et al. now show that estrogen increases pigment production in human melanocytes, and progesterone decreases it. For hormones to signal to cells, they must bind to and activate particular receptor proteins. Further investigation by Natale et al. revealed that estrogen and progesterone regulate pigment production by binding to receptors, GPER and PAQR7, that belong to a family called G protein-coupled receptors. These receptors can signal rapidly once activated by sex hormones, and may serve as therapeutic targets for treating pigmentation disorders.