Structure the NiV-F trimer.

The NiV-F trimer has a tree-like overall shape with the three copies of the F glycoprotein (colored in blue, green and violet) twined around a central axis (Axis-T). The fusion Peptide (FP) is colored in red. The NiV-F trimer is shown viewed from side, and from the top. Glycosylation moieties and disulfide bonds are shown as sticks. The inset shows a close-up view of the FP, which is located at the N-terminus of the F1 subunit, and docks into a groove formed by the F2 subunit of a neighboring F molecule within the trimer. Furthermore, the C-terminus of F2 and N-terminus of FP fold into a β-hairpin conformation, forming a continuous β-sheet (strands S1-S6) with the F1 subunit, which fixes the position of FP and stabilizes the pre-fusion state. The N-terminal FP residue, L110, is shown as a red sphere.