FIG 3.

Interactions and structural details in the immature RSV lattice. (a) Flexible fit of RSV-CA into the EM density. Helices are numbered. An arrow indicates the position at which contacts are formed between the helices 9 in the vicinity of Pro426/Val427. The density for the helix-7/helix-8 linker is visible. (b) The CA-CTD forms interactions around the hexameric ring. Residues in the MHR (green) contribute to these interfaces. The putative 6-helix bundle (45) (purple) has been fitted into the density. (c) Isosurface representation of the density corresponding to RSV-SP shown in a side view of the VLP, with the six-helix bundle model generated for RSV-SP (45) fitted into the density. The dashed line indicates the approximate position of the cleavage site between CA and SP.