The zic1 gene is expressed in chick somites but not in migratory neural crest

Zic transcription factors regulate the expression of neural and neural crest-specific genes and are expressed in the cells of the dorsal neural tube and the premigratory neural crest. Here we characterize zic1 expression in the chick embryo during somite formation and neural crest migration. zic1 is expressed in the dorsomedial portion of epithelial somites and subsequently in the dorsomedial lip of the dermomyotome. Although zic1 is expressed in cells of the nascent myotome, it is absent from differentiated myotome cells that express myosin. As the dorsal root ganglia form, zic1 is expressed at high levels in the dorsal sclerotome and zic1 expression is more pronounced in the caudal regions of the somites. Double-label experiments showed that cells expressing zic1 are not labeled by the HNK-1 antibody specific for migratory neural crest cells. Thus, migrating neural crest cells do not express zic1.