ZO-2 determines cell membrane localization of receptor NTCP and supports hepatitis B virus infection

Although a number of candidates have been reported to bind to the hepatitis B virus (HBV) envelope, accumulating evidence indicates that NTCP is accepted as a functional receptor for HBV infection. Thus, NTCP is an attractive target for antiviral therapies. Here, we showed that ZO-2 interacts with NTCP. The silencing of ZO-2 decreased HBV infection, whereas ZO-1 and ZO-3 knockdown had no effect on HBV infection. Moreover, knockout of ZO-2 induced the downregulation of NTCP from the cell surface. This aberrant NTCP localization causes the reduction of the half-life of NTCP in ZO-2 knockout cells. PreS1 treatment or HBV infection disrupted the NTCP/ZO-2 complex through the dissociation of the actin-binding domain of ZO-2, leading to internalization of a newly formed preS1/NTCP/actin complex into the cell. The actin polymerization inhibitor latrunculin A suppressed HBV infection. These results suggest that ZO-2 regulates cell surface localization of NTCP.