FIG 1.

(A) Numbers of independent amino acid replacements into each position of the capsid regions of all 403 Nigerian VDPV2 variants isolated from 2005 to 2011. VP4, shown joined with VP2 (as in its uncleaved precursor, VP0), is structurally homologous to the N termini of VP3 and VP1. Amino acid replacements in NAg sites are shown in red. H.Var, the hypervariable N-terminal residues at VP1 positions 1 to 32 (1001 to 1032). (B) Detail of Fig. S3B in the supplemental material mapping amino acid replacements in NAg sites onto the branch structure of the MCC tree (13) for lineage group 2005-8. Amino acid residues are indicated by four-digit numbers; the first digit is the name of the viral protein (4, VP4; 2, VP2; 3, VP3; 1, VP1), followed consecutively from residue 1 of each protein.