β-Endorphin: The Forgotten Hair Follicle Melanotropin

The proopiomelanocortin (POMC) gene and protein are expressed principally in the pituitary and brain (e.g., hypothalamus). The POMC gene, protein, and derived peptides, however, can also be detected in the skin. It appears that POMC can also be processed in the skin, a tissue that also expresses the prohormone convertases PC1 and PC2 and 7B2 protein.