Transcriptional regulation at the neural plate border.

摘要: The neural crest (NC) is usually defined as a cell type arising at the border of plate and epidermis in vertebrate embryos. While accurate, this definition implies that exists distinct boundary, which not really case. Like other domains early embryo, NC sharply delimited territory, but rather an overlapping zone specification has characteristics both plate, with additional its own. This can be seen spatial pattern regulatory factors have been implicated induction, many are shared.1 For example Msx1 AP2 also expressed epidermis, lower levels, c-myc likewise transcribed addition to NC. Nor limited factors. epidermal keratins, constitute intermediate filament cytoskeleton cells NC, level than epidermis. by situ hybridization (Fig. 1A) region relatively weak significant signal cranial region. Another indication fuzzy nature comes from lineage mapping experiments chick show fated differentiate placodal derivatives all intermingled neural-epidermal boundary region.2 there always clear gap visible between gene expression domains, for double keratin pan-neural marker NCAM two contiguous 1B). Expression genes evident animal caps dissected embryos injected BMP antagonists, such chordin, along canonical Wnt molecule, Wnt3a.