Expression of c-kit encoded at the W locus of mice in developing embryonic germ cells and presumptive melanoblasts
. Dev Biol.
Reams, "The development of melanoblasts
from leg bud mesenchyme grown in the celom of chick embryos," Annals of Anatomy, vol.
migrate from the neural crest to the epidermis and hair follicles, where they differentiate and become mature melanocytes that synthesize melanin.
The c-kit gene affects the differentiation and migration of melanoblasts
from the neural crest during embryonic life.
It is characterized by the congenital absence of melanocytes in the affected areas of skin and hair, due to mutations of the KIT proto-oncogene, which affects the differentiation and migration of melanoblasts
It has been shown that Notch signaling, mediated in rodents by the RBP-Jk transcription factor (homologous to human CBF1), is necessary for self-maintenance of melanoblasts
and melanocyte stem cells .
Nuclei of neoplastic melanoblasts
are hyperchromatic, large, with lumpy chromatin and one or more prominent nucleoli.
invade the epidermis between day 11 and 12 of gestation, complete colonisation in the epidermis by day 13 or 14, and differentiate into active melanocytes at day 16.
Melanomas originate from neuroectodermal melanoblasts
, which migrate at the beginning of the development period into the epidermal-dermal junction of the skin, follicles, and dermis.
In very early embryogenesis, the first group of neural crest cells gives rise to melanoblasts
, which migrate over the surface of the embryo, and from which are derived the fully formed melanocytes.
In their study, they utilized primary mouse neural crest cells (NCCs) obtained from E8.5 GFP expressing embryos from C57BL/6 background and injected these cells into a nonpigmented [W.sup.sh]/[W.sup.sh] c-Kit mutant mouse lacking endogenous melanoblasts
. They then examined the coats of postnatal mice for pigmentation which would arise only from the donor cells, which was confirmed by checking for GFP.