Figure 3. Binding of ESCRT-III by Vps4.

Successive ESCRT-III dipeptides are shown bound at the interfaces between the helical Vps4 subunits in equivalent orientations. The odd-numbered (1, 3, 5, 7) residues of the bound ESCRT-III octapeptide bind to class I pockets between the pore loop 1 tryptophan (W) residues of successive Vps4 subunits. The even-numbered (2, 4, 6, 8) residues bind to class II pockets between the pore loop 1 methionine (M) residues of successive Vps4 subunits.