FIG. 4.

G-to-A mutation spectrum of viral DNA in H9 cells and PBMCs. Shown are nucleotides 7057 to 7522 of the 466-bp env fragment of HIV-1 NL4-3, which was cloned and sequenced. The V3 and V4 loops are underlined, and all first guanine residues of the GG motifs, which are preferentially targeted by APOBEC3G, are depicted in bold. Given in red are the percentages of guanine residues mutated to adenine in a total of 290 HIV-1 env sequences obtained by the infection of H9 cells (95 clones) and PBMCs from four different donors (195 clones) harboring at least one G-to-A mutation. Percentages of G-to-A mutations within GA motifs, which are the preferred motifs of APOBEC3F, are depicted in black when more than 5% of those motifs have been mutated.