Regulation and function of Dlx3 in vertebrate development

Dlx3 is a homeodomain transcription factor in vertebrates, related to Dista l-less in Drosophila, that is expressed in differentiating epidermal cells, in neural crest, hair follicles, dental epithelium and mesenchyme, the oti c and olfactory placodes, limb bud, placenta, and in the cement gland, whic h is located in the extreme anterior neural plate in Xenopus embryos. This factor behaves as a transcriptional activator, and positively regulates gen e expression in the skin, and negatively regulates central nervous system m arkers in Xenopus epidermis and anterior neural plate. A mutation in the DL X3 gene is associated with a hereditary syndrome in humans, and loss of Dlx 3 function is a developmental lethal in gene-targeted mice, where it is ess ential for proper modeling of the labyrinthine layer of the placenta. In th is review, we discuss the evolution, expression, regulation, and function o f Dlx3 in mouse, amphibians, and zebrafish, Published 2000 Wiley-Liss, Inc. dagger.