SNARE proteins

These are four proteins involved in membrane fusion events. Alanine residues are colored red. Leucine residues are colored blue. Notice that the helices appear to be more loosely bound together than in a typical coiled-coil.

Early endosomal SNAREs form a structurally conserved SNARE complex and fuse liposomes with multiple topologies.
Zwilling D, Cypionka A, Pohl WH, Fasshauer D, Walla PJ, Wahl MC, Jahn R.
EMBO J. 2007 Jan 10;26(1):9-18
(PubMed)

2nps (PDB)