Murine genes with homology to Drosophila segmentation genes

As a potential method to define genes that control vertebrate segmentation processes during embryogenesis, murine genes containing a protein domain homologous to the Drosophila paired box sequence were isolated. The mouse genome contains at least three genes with highly conserved paired box like sequences, termed Pax genes, that are also conserved in other vertebrates. During embryogenesis, the Paxl gene is expressed in ventral sclerotome cells and in the intervertebral disks of the vertebral column. Thus, Paxl clearly shows a segmented pattern of expression. A second gene, Pax2, also is expressed in segmented structures of the intermediate mesoderm and in certain regions of ectoderm derived tissues. The Paxl and Pax2 genes map to chromosomes 2 and 7, respectively. Interestingly, several known mutations that affect vertebral column development map near the Paxl locus.