A human cell polarity protein Lgl2 regulates influenza A virus nucleoprotein exportation from nucleus in MDCK cells

In this study, the regulatory effect of the overexpression of polarity protein Lgl2 on the nuclear export of influenza A virus nucleoprotein in infected cells was investigated. A stable Tet-Off inducible MDCK cell line expressing a fusion protein comprising Lgl2 and an enhanced yellow fluorescent protein were used. TCID 50 analysis and neuraminidase activity analysis revealed that replication of influenza A virus was inhibited in Lgl2 overexpressing cells. By immunofluorescence microscopical observation at different time point post virus infection, a retention of NP in cellular nucleus was found in Lgl2 overexpressing cells. Compared with normal MDCK cells, change in claudin-1 distribution between cell contacts caused by Lgl2 overexpression impaired the barrier function of tight junction. These results suggest that changes in cell polarity induced by Lgl2 overexpressing will affect virus NP transportation.