Figure 4

Multiple sequence alignment of amino acids of env from FIV _Ple subtypes B and E compared with FIV _Fca subtypes A, B and C, FIV _Pco subtypes A and B, and FIV _Oma . Significant structures within the env gene inferred from Smirnova et al. 2005 are indicated in colored boxes. Putative regions include: conserved amino acids (white box), variable regions V1-V9 (red box); epitope binding sites (orange box); conserved cysteine (red highlight); N glycosylation sites (yellow highlight). Homologous region shared between FIV _Ple subtypes B and E are highlighted in grey. Amino acid sites 1–176 contain the first exon of rev (see Table 1) in lion FIV _Ple subtypes B and E. The portion of env proposed to be a result of recombination in FIV _Ple subtype E is highlighted in green. The corresponding region of env thought to represent FIV _Ple without recombination, as it is more homologous to FIV _Oma , is highlighted in blue. Amino acids sites 931–978 (grey) likely contain the RRE element shared by lion FIV _Ple subtypes B and E.