Analyses of neuronal and epithelial cell polarity of mice lacking genes involved in polarized transport

Akihiro Harada
Department of Cell Biology, Graduate School of Medicine, Osaka University

Cell polarity of neurons and epithelial cells is established and maintained by polarized transport within cells. A number of genes have been known to be necessary for polarized transport in vitro, but it is not known when and where they are required in vivo. We generated mice deficient in genes involved in polarized transport, such as Rab8a and Rab8b. We analyzed their brains and epithelial tissues to find abnormalities in cell polarity. For Rab8a and Rab8b, we already generated single and double knockout (KO) mice. Rab8b KO mice showed no overt abnormalities. Rab8a KO mice and Rab8a,b double KO mice showed defects in cell polarity in epithelial cells in the small intestine. In particular, various apical markers are mislocalized in the knockout cells. However, they did not show defects in neuronal polarity and polarized tranport of a dendritic marker in the cerebellum. From these results, it is indicated that the mechanism of polarity differs between epithelial cells and neurons. We are now analyzing other genes involved in polarized transport (PKD1,2, FAPP1,2, syntaxin3, Rab11a) and the preliminary results will be presented in this meeting.
This research is supported by KAKENHI(24390046).

References
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