Fig. 8.

Model of ORF2i protein addressing to viral factories by AP-1 complex. Newly produced ORF2i proteins are anchored in secretion pathway membranes through their Nter and oriented toward the cytosol. ORF2i protein then interacts with AP-1 complex in TGN to generate ORF2i protein/AP-1 complex-positive transport vesicles, in a clathrin dependent-manner. The transport vesicles transit to the endosomal recycling compartment (ERC) that constitutes viral factories where ORF2i protein colocalizes with the ERC resident marker Rab11. The enrichment of ORF1, ORF2i, ORF3 proteins and viral RNA in viral factories leads to viral assembly and production/secretion of infectious HEV particles. The inhibition of AP-1 complex activity either by A5 molecule or by silencing the AP-1γ1 adaptin (siAP-1γ1) prevents the ORF2i protein/AP-1 complex interaction, resulting in the absence of AP-1-positive vesicles containing ORF2i protein. In this context, ORF2i protein is no longer addressed to ERC/viral factories and does not colocalize with Rab11. Such process likely interferes with viral assembly, resulting in a significant reduction of infectious HEV particles production/secretion and ORF2i protein detection in culture supernatant