Regulation of Dlx Homeobox Gene Expression During Development of the Zebrafish Embryo

The comparison of gene structure, function, and regulation of gene expression in distant species constitute powerful tools to enhance our knowledge of the evolution of multigene families and to shed light on fundamental mechanisms of development. In our studies of the dlx family of homeobox genes in the zebrafish, we have compared the sequences, embryonic expression patterns and genomic organization of the zebrafish dlx genes with those of other vertebrates and suggest that conservation of shared cis-acting regulatory sequences in pairs of dlx genes constitute a key element of their coordinated expression during development. Our studies show the importance of analyzing developmental genes in teleost fish to understand the evolution of gene families and elucidate developmental strategies.