THE CENTRAL STRUCTURAL FEATURE OF THE MEMBRANE-FUSION PROTEIN SUBUNITFROM THE EBOLA-VIRUS GLYCOPROTEIN IS A LONG TRIPLE-STRANDED COILED-COIL

The ectodomain of the Ebola virus Gp2 glycoprotein was solubilized wit h a trimeric, isoleucine zipper derived from GCN4 (pIIGCN4) in place o f the hydrophobic fusion peptide at the N terminus. This chimeric mole cule forms a trimeric, highly alpha-helical, and very thermostable mol ecule, as determined by chemical crosslinking and circular dichroism. Electron microscopy indicates that Gp2 folds into a rod-like structure like influenza HA2 and HIV-1 gp41, providing further evidence that vi ral fusion proteins from diverse families such as Orthomyxoviridae (In fluenza), Retroviridae (HIV-1), and Filoviridae (Ebola) share common s tructural features, and suggesting a common membrane fusion mechanism.