Figure 5.

Human immunodeficiency virus (HIV)-1/-2 capsid sequence variations and epitopes of cytotoxic T lymphocytes (CTL). The amino acid sequences of the NL4-3 CA (amino acids 85–140) and GH123 CA (amino acids 82–140) are shown. The loop between α-helices 4 and 5 (L4/5) and the loop between α-helices 6 and 7 (L6/7) are underlined. The CTL epitopes are indicated in pink (TW10), sky blue (KK10), and green (NY9). Amino acid residues that are commonly mutated and were mentioned in this review are indicated. The amino acid residues are numbered both according to the amino acid residues in CA and the whole Gag precursor polyprotein (numbers in parentheses). Cyclophilin A (CypA) catalyzes the 90th proline residue of HIV-1 CA, and alanine residue at the 88th position is critical for CypA binding (Price et al., 2009).