@phdthesis{oai:tsukuba.repo.nii.ac.jp:00008357,
 author = {安達, 在嗣 and Adachi, Yoshitsugu},
 month = {},
 note = {Molecular mechanisms of cephalic development is an intriguing question in evolutionary and developmental biology. Otx gene plays important roles in animal brain and head development and Otx genes are found in all major animal groups: cnidarians, lophotrochozoans, ecdysozoans, and
deuterostomes. Ascidians, positioned near the origin of the phylum Chordata, share a conserved set of anteroposterior patterning genes with
that of vertebrates. Here I report the cross-phylum regulatory potential of the ascidian Otx gene in the development of the Drosophila brain and the head vertex structures. The ascidian Otx gene rescued the embryonic brain defect of Drosophila caused by null mutation of the orthodenticle (otd) gene and enhanced rostral brain development while it suppressed trunk
nerve cord formation. Furthermore, the ascidian Otx gene restored the head vertex defects caused by a viable otd mutation, ocelliless, via specific
activation and repression of downstream regulatory genes. The crossphylum regulatory potentials of the ascidian Otx gene are equivalent to the activities of the Drosophila and human otd/Otx genes in these developmental processes. In contrast to these results, cnidarian Otx gene showed little functional equivalence in Drosophila. In addition, planarian
Otx gene had failed to rescue Drosophila embryonic brain development. The results with ascidian Otx gene function support the notion that
basal chordates such as ascidians have the similar molecular patterningmechanism for the anterior structures found in higher chordates, and
suggest a common genetic program of cephalic development among invertebrate, protochordate and vertebrate.  ･･･, 2003, Includes bibliographical references},
 school = {筑波大学, University of Tsukuba},
 title = {Cross-phylum functional equivalence of Otx genes and the origin of brain patterning},
 year = {2004}
}