Department of Anatomy(Histology and Embryology)

Polypterus,a model animal for studying tetrapod evolution The evolutionary transition from aquatic vertebrates to terrestrial tetrapods occurred around 370 million years ago in the late Devonian period. What changes in genome function caused such evolution and led to the development of new organ remains uncertain. We have been investigating the evolution of the tetrapod body plan using a primitive actinopterygian fish,Polypterus senegalus, with analyses of comparative anatomy,comparative developmental biology,and comparative genomics. In collaboration with Professor Asao Fujiyama of the National Institute of Genetics,we have performed expressed sequence tag analyses of Polypterus embryos at stages later than neurulation. We have determined nucleic acid sequences of more than 50,000 clones and annotated each sequence by tBlastn analyses.