Pax genes, mutants and molecular function.

The paired domain is a conserved DNA binding motif which was first found in Drosophila segmentation gene products. This paired domain is encoded by a well conserved, paired box DNA sequence, also detected in the genomes of other species. The mouse paired box-containing genes are referred to as Pax genes and are expressed in a distinct spatiotemporal pattern during embryogenesis. Pax proteins are able to bind to specific DNA sequences and modulate transcriptional activity. Interestingly, three different Pax genes have already been shown to correspond to some mouse and human mutants, emphasizing their role as developmental control genes.