Fig 4.

The BV phenotype. The illustration on the left side represents a dissected view of the structure of the BV. The DNA genome is shown expanding from the nucleocapsid in order to emphasize its presence in the nucleocapsid. The major BV envelope fusion proteins (EFPs), GP64 and F protein are shown at the upper peplomer end of the virion. This illustration is in the context of a group I NPV baculovirus. The right hand side illustrates the processes of BV egress from an infected cell (lower right) and BV infection of a new cell (upper right). Nucleocapsids bud out of the infected cell membrane where viral EFPs have concentrated. In budding, the virion acquires EFPs and the cell membrane as its virion envelope. The BV diffuses across to a new cell where it is taken into the cell by receptor‐mediated endocytosis. The BV‐containing endosome fuses with an acidifying lysosome. This pH shift triggers EFP‐mediated envelope fusion with the endosomal membrane and release the BV nucleocapsid into the cytosol. The nucleocapsid then translocates to the nucleus.