Localization Of IPO13 In Neural Development

Nulceocytoplasmic transport of macromolecules is mediated by soluble transport receptors, namely importinβsuperfamily proteins. Recently, some members of this superfamily are shown to function in development. In the study of molecular mechanisms of lung organogenesis, a novel importinβhomolog, importin13 (IPO13) was isolated. IPO13 has been identified to be the only bi-directional transporter in this family in mammal. Most of its isolated cargoes are related to development, suggesting its roles in development.To study IPO13, we expressed and purified full-length IPO13 and produced an anti-IPO13 polyclonal antibody. This antibody was purified and its specificity was proved. By using this antibody, we found the distribution of IPO13 is different in neural tissues at different developmental stages. In the early stage, most IPO13 localizes in the cytoplasm but at the late stage and in adults IPO13 is mainly in the nucleus in nerve cells.At the early stage of development, neuroepitheliuia proliferate continuously. At the later stage, neuroephitheliuia differentiate into the neuroblast cells. We conclude that the distribution of IPO13 in nerve cells is regulated developmentally and IPO13 may play different roles in neural development by changing its subcellular distribution.