(A) Radially colored cryo-EM density map of the HSV-1 capsid viewed
along a threefold axis. Fivefold, threefold, and twofold axes are denoted by a
pentagon, triangle, and oval, respectively. (B) Magnified view of
one facet of the icosahedral capsid with structural components differentially
colored. The density of triplex Tf at the center is not shown. (C)
A schematic representation of one asymmetric unit (shaded) of the capsid. An
extra copy of triplex Te (unshaded) from an adjacent asymmetric unit is shown to
depict that triplex pair Tb-Te has a similar configuration as Ta-Tc, thus
providing a second potential binding site for the CATC (11, 17). The
enlarged red and blue triangle shows the heterotrimeric nature of a triplex.
a.a., amino acid. (D) Atomic models of individual capsid or
tegument proteins in rainbow-colored ribbon (from blue at the N terminus to red
at the C terminus). Numbers denote chain termini or flexible segments that are
not modeled. a.a., amino acid.