Figure 1.

The components of the influenza virus, and the steps of viral replication Viral attachment and entry into the cell occur via the endosomal pathway. Acidification of the endosome promotes viral membrane fusion and activates the M2 ion channel, which pumps protons (H⁺) into the interior of the viral core to initiate uncoating of the M1 protein. Nuclear replication occurs, and viral gene products are transported to the plasma membrane for assembly. Nascent virions are assembled at the apical domain of the plasma membrane, and complete virus particles bud and are released from the cell (27).