Fig. 2

The S40A mutation in Gag alters the amino acid sequence at the p6*-PR cleavage site in the overlapping pol frame. a Schematic drawing of HIV-1 gag, pol gene organization showing the region of overlap. The C-terminal region of the gag gene encodes L domain-1 (P₇TAP₁₀) and L domain-2 (₃₅LYPLTSL₄₁). Residue S40 in the latter motif is highlighted. This region of gag overlaps with the N-terminal region of the pol gene that encodes the N-terminal cleavage site of PR (SFSF₅₆/PQIT). b The substitution of A for S40 in the gag reading frame (red font) alters the sequence encoding the N-terminus of PR in the pol reading frame (blue font). p6 S40A is Gag S488A (HXB2 numbering)