Figure 4.

Receptor binding and the antigenic landscape of GP. (a) Left: Side view of a surface representation of the LASV GP trimer is shown with N-glycosylation sites shown as blue spheres. The GP1 subunit is colored light gray and the GP2 subunit colored dark gray. The TfR1 binding site for pathogenic New World arenaviruses such as MACV and JUNV has been mapped onto the LASV GP structure and is colored light blue; the LAMP1 binding site (as it exists in the context of the trimer) is colored purple. Right: The top view of the trimer highlights residues involved in binding to the LASV and LCMV receptor αDG (yellow) [22, 23, 24,41,51]. Note that for LASV and LCMV GPC, not GP1 alone, is required for cell surface receptor binding [41,52]. Hence, a quaternary assembly of GP1, provided only in the context of the GPC, may be necessary for αDG engagement. (b) LASV neutralizing antibody epitopes are colored by epitope group: GP1-A, which recognizes the GP1 subunit alone is colored green; GPC-A, which recognizes a single prefusion GP monomer is colored purple; GPC-B, which recognizes a quaternary epitope that spans two GP monomers within the trimer is colored peach. Neutralizing antibodies against JUNV GP1 are colored yellow and partially overlap with those of the LASV GP1-A group.