Y. Katagata et al., Keratin subunit expression in human cultured melanocytes and mouse neural crest cells without formation of filamentous structures, J INV D SYM, 4(2), 1999, pp. 110-115
Citations number
35
Categorie Soggetti
Dermatology
Journal title
JOURNAL OF INVESTIGATIVE DERMATOLOGY SYMPOSIUM PROCEEDINGS
The synthesis of keratin is considered to occur in epithelial and epidermal
cells. Previous studies have not reported on keratin synthesis within mela
nocytes that derive from neural crest cells. Epithelial and neural crest ce
lls originally develop from ectodermal tissue. We previously reported that
the expression of keratin is a universal phenomenon seen in cultured melano
ma cell Lines, as demonstrated by two-dimensional polyacrylamide gel electr
ophoresis, western blot, and electron microscopy analyses, To further inves
tigate the specificity of keratin function in melanocytic cells, we first e
xamined the presence of keratin proteins in cultured human melanocytes, and
unexpectedly found keratin subunits in melanocytes by the above-mentioned
procedures, The keratin (K) subunits were composed of K1, K5, K8, K10, K14,
K16, and K18, together with vimentin, Neural crest cells, which contain im
mature embryonic melanocytes developing from ectoderm, already expressed ke
ratins; however, under electron microscopy, the expressed keratin did not f
orm filamentous structures, Although the ATP synthase alpha-chain, which is
expressed universally in cultured epidermal tumor cell lines, was also exp
ressed in cultured melanocytes and neural crest cells, a novel malignant me
lanoma-related protein (MMRP) was absent in melanocytes and neural. crest c
ells. We concluded that keratin subunits are present in both cells, but do
not construct keratin filaments.