CULTURED HUMAN MELANOCYTES EXPRESS THE INTERMEDIATE FILAMENT VIMENTIN

Human melanocytes are neural crest - derived cells that synthesize the pigment melanin. These cells migrate from a central location to the d ermal-epidermal junction early in gestation and situate themselves bet ween keratinocytes of the basal layer of the epidermis, extending thin dendritic processes upwards into the epidermis. In vitro, neonatal me lanocytes can assume a variety of morphologies, depending on the cultu re conditions. Using standard immunofluorescent, immunoblotting, and N orthern blotting techniques, we investigated the expression of interme diate filament proteins and demonstrate here that cultured human melan ocytes express vimentin gene and protein under a variety of culture co nditions. Vimentin is a 57-kD intermediate filament protein synthesize d primarily by cells of mesenchymal origin. It is transcribed as a sin gle-messenger RNA species of 2.0 kb and the human gene is located on c hromosome 10. As a member of the intermediate filament family of prote ins, we suggest that vimentin is an important component of the cytoske leton of neonatal, human melanocytes.