Steel factor is required for maintenance, but not differentiation, of melanocyte precursors in the neural crest.
Skin melanocytes are derived from neural crest cells that migrate into the dermis during embryogenesis. Two mouse mutants, Steel and White dominant-spotting, which have defects in melanocyte production, have recently been shown to have deletions in the genes that code for a new growth factor, steel factor (SLF), and its receptor, respectively. Here, we have investigated the role that SLF plays in melanogenesis using cultures of mouse neural crest and found that its primary action is the maintenance of melanocyte precursors. It has no effect on the final stage of melanocyte differentiation, the production of melanin, which appears to require an additional factor whose action is mimicked by the phorbol ester TPA (12-O-tetradecanoyl-phorbol-13-acetate).
Murphy
M
M
Walter and Eliza Hall Institute of Medical Research, Royal Melbourne Hospital, Parkville, Victoria, Australia.
Reid
K
K
Williams
D E
DE
Lyman
S D
SD
Bartlett
P F
PF
D000818:Animals; D002452:Cell Count; D002478:Cells, Cultured; D016298:Hematopoietic Cell Growth Factors / Q000494:pharmacology*; D008544:Melanocytes / Q000187:drug effects*; D051379:Mice; D008808:Mice, Inbred CBA; D009432:Neural Crest / Q000196:embryology*; D010703:Phorbol Esters; D019089:Stem Cell Factor; D013234:Stem Cells / Q000187:drug effects*
D016298:Hematopoietic Cell Growth Factors; D010703:Phorbol Esters; D019089:Stem Cell Factor