RT Journal Article SR Electronic T1 Hox genes pattern the primary body axis of an anthozoan cnidarian prior to gastrulation JF bioRxiv FD Cold Spring Harbor Laboratory SP 219758 DO 10.1101/219758 A1 Timothy Q. DuBuc A1 Thomas B. Stephenson A1 Amber Q. Rock A1 Mark Q. Martindale YR 2017 UL http://biorxiv.org/content/early/2017/11/14/219758.abstract AB Hox gene transcription factors are important regulators of positional identity along the anterior-posterior axis in bilaterian animals. Cnidarians (e.g. sea anemones, corals and hydroids) are the sister group to the Bilateria and possess genes related to both anterior and central/posterior class Hox genes. In the absence of a conserved set of Hox genes among other early branching animal clades, cnidarians provide the best opportunity to learn about the emergence of this gene family. We report a previously unrecognized domain of Hox expression in the starlet sea anemone, Nematostella vectensis, beginning at early blastula stages. Functional perturbation reveals that two Hox genes not only regulate their respective expression domains, but interact with one another to pattern the entire oral-aboral axis mediated by Wnt signaling. This suggests an ancient link between Hox/Wnt patterning of the oral-aboral axis and suggest that these domains are likely established during blastula formation in anthozoan cnidarians.