Irreducible Complexity of Hox Gene: Path to the Canonical Function of the Hox Cluster.

The evolution of major taxa is often associated with the emergence of new gene families. In all multicellular animals except sponges and comb jellies, the genomes contain Hox genes, which are crucial regulators of development. The canonical function of Hox genes involves colinear patterning of body parts in bilateral animals.

Maternal Transcripts of Hox Genes Are Found in Oocytes of (Annelida, Nereididae).

Hox genes are some of the best studied developmental control genes. In the overwhelming majority of bilateral animals, these genes are sequentially activated along the main body axis during the establishment of the ground plane, i.e.