This animation shows the paramyxovirus fusion protein refolding event from pre to post fusion.
Sialic acid binds to one of the heads of the HN protein (left), tugging it upwards, revealing the HN stalk. The HN stalk then interacts with the F protein (right), cleaving F. The folding process begins with F embedding itself into the cell membrane (top) and then the domains of F zipper together, causing the viral membrane (bottom) and cell membrane to fuse together.
