The Trox-2 Hox/ParaHox gene of Trichoplax (Placozoa) marks an epithelial boundary

@article{Jakob2004TheTH,
  title={The Trox-2 Hox/ParaHox gene of Trichoplax (Placozoa) marks an epithelial boundary},
  author={W Jakob and Sven Sagasser and Stephen L. Dellaporta and Peter W. H. Holland and Kerstin Kuhn and Bernd Schierwater},
  journal={Development Genes and Evolution},
  year={2004},
  volume={214},
  pages={170-175}
}
Hox and ParaHox genes are implicated in axial patterning of cnidarians and bilaterians, and are thought to have originated by tandem duplication of a single “ProtoHox” gene followed by duplication of the resultant gene cluster. It is unclear what the ancestral role of Hox/ParaHox genes was before the divergence of Cnidaria and Bilateria, or what roles the postulated ProtoHox gene(s) played. Here we describe the full coding region, spatial expression and function of Trox-2, the single Hox… 

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